In insects, whose internal temperature is variable, whether living on vegetable or animal substances, or both, he found the urinary secretion, like that of birds, composed chiefly of lithate of ammonia, and lithic acid.

Spiders, animals of a low internal temperature, but of considerable activity, and living on insects, secrete a urine of a different kind, being composed of xanthic oxide.

In serpents, in many respects resembling the spiders in their physiological conditions, the urinary secretion is chiefly composed of lithate of ammonia. The urinary secretion in lizards appears to resemble that of serpents.

In frogs and toads, whose internal temperature is also low, and which resemble the animals last mentioned in living on animal food, and being capable of long-continued fasting, the urinary secretion does not consist, as in those, of granules of lithate of ammonia, mixed with a little watery fluid, becoming solid before, or shortly after being voided; but consists chiefly of water holding in solution urea and a little saline matter, and in its composition may be considered as an approach to the human urinary secretion.

"What are the bearings of these facts in their physiological relations? Do they not prove that neither the temperature of the animal, nor its activity, nor even its food (that is, the physiological conditions connected with respiration, muscular action, digestion, &c.), affect materially the nature, as to composition, of the urinary secretion? And does it not follow that the quality of this secretion, therefore, must depend chiefly on the intimate structure of the secerning organs?" Dr Davy states, that though he believes that the quality of the secretion from the kidneys depends chiefly on structure, yet it is affected in a minor degree by circumstances of diet, and of atmospheric temperature, especially in man. In a cold or cool climate, using a diet chiefly of animal food, lithic acid (and lithate of ammonia are found commonly, in considerable proportion, in the human urine; but not so in a hot climate, not even when the diet is the same; and in consequence, within the tropics, where least oxygen is consumed in respiration, the ailments depending on the formation of gravel and calculi are almost unknown. -Edinburgh New Philosophical Journal, January 1848.

4. Mr TURNER on the Eighth and Ninth Vertebrae of the Three-toed Sloth.Mr H. N. Turner jun., discusses the

point, whether the eighth and ninth vertebræ of the aï or three-toed sloth (Bradypus tridactylus) are to be regarded as belonging to the cervical or dorsal vertebræ, and he arrives at the conclusion that they belong to the cervical.

That those of our readers who may not have previously had their attention turned to this question, may be able to understand its bearing, we shall make a few remarks upon it. Daubenton announced that all the mammalia, whatever may be the length of the neck (in the giraffe as in the cetacea,) the number of cervical vertebræ is invariably seven, and this was universally assented to at the time. Cuvier, however, in the course of his dissections, ascertained that the aï, one of the sloths (all sloths do not present this peculiarity), had nine cervical vertebræ, and thus undermined the generalization of Daubenton. Professor Bell of London, in a paper in the Zoological Transactions, discovered that rudimentary ribs were attached to the eighth and ninth vertebræ in the aï, and he ingeniously attempted to prove that these were dorsal and not cervical vertebræ, and that Daubenton's generalization was not impaired by the structure of the aï. De Blainville, a few years ago, and Mr Turner, in the communication referred to above, have entered into various anatomical details, which appear to us to prove that the eighth and ninth vertebræ in the aï are cervical and not dorsal, and that they in fact resemble the seventh cervical vertebra in man. It is well known that the seventh cervical vertebra in the human species is occasionally provided with rudimentary ribs, and Mr Turner found rudimentary ribs attached to the same vertebra in a pole-cat. De Blainville has ingeniously arranged the cervical vertebræ into three groups: The first includes the atlas and axis: The second-the third, fourth, fifth, and sixth ; the third includes only the seventh in the human species, and almost all the other mammalia; but in the aï includes three vertebræ, viz. the seventh, eighth, and ninth.-Annals of Natural History, December 1847.

5.-On the Jalap Plant which has lately flowered in the Edinburgh Botanical Garden. By Professor BALFOUR.-Although jalap has been used in European medicine for nearly two centuries and a half, it is only within a few years that its botanical source has been correctly ascertained. The plant long cultivated as the true jalap plant in the stoves of Europe, and among the rest in the Botanic Garden of Edinburgh, is the Convolvy

lus Jalapa of Linnæus and Wildenow, or Ipomea macrorhiza of Michaux, a native of Vera Cruz. But between the years 1827 and 1830, it was proved by no fewer than three independent authorities, that the root of commerce is obtained, not from the hot plains around Vera Cruz, but from the cooler hill country near Jalapa, about 6000 feet above the level of the sea, where it was exposed to frost in the winter time; and that the plant which yields it, is an entirely new species of the Convolvulaceæ. In this country it was probably first cultivated in the Botanic Garden of Edinburgh, from a tuber sent by Dr Coxe of Philadelphia to Dr Christison, in 1838. Dr Graham could not describe it at that time, because, owing to unacquaintance with the habits of the plant, it was forced in the stove, and died the same year, after forming numerous flower-buds,

of which one only became partially developed. In 1844, a plant from the Chelsea Botanic Garden, cultivated in a cold frame in the Edinburgh garden during the winter and spring, survived in the summer and autumn, and flowered luxuriantly in September. But the crown of the tuber was injured by frost in the subsequent winter, and the tuber was thus killed. Ultimately, Mr M'Nab resolved to try whether the plant could be reared from slips; and the experiment has proved successful. A tuber, of the size of a hazel nut, formed in the course of three months. The stem made little progress next summer; but when transferred to the cold frame in the spring of 1846, formed the plant which flowered in October.-Edinburgh New Philosophical Journal, January 1848.

;

6.-On the Nucleus of the Animal and Vegetable Cell. By Dr MARTin Barry · Schleiden ascribed to the nucleus of the vegetable elementary cell the power of forming around it a membrane which became the cell-membrane or cell-wall hence he gave to the nucleus the name of cytoblast. But with the formation of the cell-wall he conceived the function of the nucleus to cease; and thought that, being no longer required, it became inert in the cell-wall, or in some instances was absorbed. The nucleus itself was, in the first instance, produced by a similar mode of development, being deposited around a smaller body, which sometimes remained as a permanent nucleolus. The same view of the formation of cells was advocated in relation to the animal tissues by Schwann, Müller, Henle, and Valentin, the last of whom thus describes the process :-" In a fluid there are precipitated granules, which are nucleoli; around the nucleolus there is deposited a finely granular substance, by which there is formed the nucleus (cytoblast); and around the nucleus there is formed the membrane of the cell. The principle of formation of the nucleus around the nucleolus, is essentially the same as that of the cell around the nucleus."

To borrow the language of the botanist, the preceding physiologists consider the vegetable animal cell to have an "exogenous" development; the primitive nucleolus remaining central, and the subsequent formations being deposited layer by layer around the nucleolus, which, so

long as it remains at all, retains the same relative position. This view Dr Barry conceives to be incorrect, and propounds a theory of cell-development which corresponds much more closely with the type of structure called in botany "endogenous." Dr Barry describes the development of the cell as being analogous to that of the mammiferous ovum. According to him the original granule or nucleolus gradually enlarges, and in time develops within it a second body, which, appearing at first as a pellucid point, comes to occupy the position and assume the form of the original nucleolus, which has now expanded into a nucleus (the cytoblast of Schleiden). Thus the primitive formation becomes peripheral, while the secondary nucleolus occupies the central position. The same law is pursued in the further development. The nucleus or cytoblast becomes a cell, and the secondary nucleolus becomes in its turn a nucleus by the development within it of a tertiary formation, which assumes the position and functions of the nucleolus. In the complete cell thus formed there are three parts-1st, the cell-membrane, or cell-wall of Schleiden, which is the original or primary nucleolus; 2d, the nucleus (cytoblast of Schleiden), which is the secondary nucleolus; 3d, the true nucleolus of Schleiden, which is the tertiary or last developed nucleolus of Dr Barry.

According to this theory, therefore, cells are developed endogenously; the first formed parts being always found at

finally, stoppage, with accumulation of the corpuscles, behind the obstruction. On the galvanic stimulus being removed, the circulation gradually returned to its natural condition.-Müller's Archiv., 1847, No. 2.

9.-The Functions of the Spleen, and Constitution of Venous Blood in different Parts of the System. By M. BECLARD.It is, from many circumstances, probable that the spleen is an organ intended, in some way or other, to operate upon the blood which passes through it; and in order to ascertain whether any, or what changes, are produced by it, M. Beclard has performed a series of analyses of venous blood, the results of which he has here detailed, and which lead to conclu

sions of a very remarkable character. His experiments entirely disprove the opinion of Donné, that the spleen is the organ by which the blood-globules are formed; as he has found that the blood of the splenic vein (previous to its junction with the vena portæ and veins of the stomach) contains a quantity of globules, inferior not merely to arterial, but even to the average of that contained in venous blood generally. On the other hand, the proportion of albumen is increased.

The examination of the blood of the vena portæ shows a very large proportion of globules, and a corresponding diminution of the albumen, as is clearly shown by the following table :

tem.

M. Beclard is still engaged in the prosecution of these experiments; and his present communication appears to be merely the announcement of an extended investigation, which, should the first results be borne out, is likely to throw an important light on the functions of the abdominal organs.-Annales de Chemie et de Physique, December 1847.

10.-Influence of Common Salt on the composition of the Blood. By M.PLOUVIEZ. -M. Plouviez considers common salt to be a tonic, and to possess the power of modifying the constitution of the blood; and states, that he has employed it with great advantage in scrofula, anemia, and chlorosis. In order to establish the effect which it produces, he analysed his own blood at two different periods, during the first of which he took daily ten grammes of salt more than usual, and the second, after he had ceased for two months to take this unusual quantity, and with the following results :

First Second Period. Period. 767-60 779.92 143:00 130:08

2.25

74:00

1:31 11:84

1000 00

2:10

77:44 1:13 9:33

1000 00

Substances soluble in water.

Chloride of Sodium,

Potassium,

Phosphate of Soda,

Sulphate of Soda,

Alkaline Carbonates,

Loss,

6:10

4:40

0:30

0.27

11.-On the Digestion of Alcoholic Drinks, and their Function in Nutrition. By MM. BOUCHARDAT and SANDRAS.The authors have performed a series of experiments, with the view of ascertaining the mode in which alcohol is absorbed, and the changes which it undergoes in the system. Their first experiments were made upon dogs, which were killed two hours after the administration of a quanThe chyle and blood tity of alcohol. were separately examined for that fluid, which was found totally absent in the former, but present in minute quantity in the latter. Acetic acid was also detected

in the blood by distillation with sulphuric acid, after the separation of the alcohol which it contained.

Owing to the difficulty in getting dogs to take spirituous fluids, they afterwards made use of fowls and ducks; and it was was found that, in most cases, where the blood was taken sufficiently soon after the administration of the alcohol, both that substance and acetic acid could be detected in it in minute quantity. Very rapid absorption also takes place, and in one experiment, the authors found that three-fourths of the spirit administered was absorbed in less than twenty minutes.

It was then ascertained that the quantity of alcohol which escapes by the lungs is quite inconsiderable. This was determined by directing the gases and vapours evolved during respiration, by a man who had taken a considerable dose of alcohol, through a Woulff's bottle, surrounded by a freezing mixture. After the operation had been conducted for two hours, only a minute quantity of alcohol was found in

the condensed fluid. None escaped by the urine or other secretions.

In the case of a man who, after a three days' debauch upon strong punch, was seized with a succession of epileptic fits, they found that blood drawn immediately from the jugular vein contained both alcohol and acetic acid in small quantity, while that taken an hour later contained none. They found, however, by Frommherz's test, distinct indications of the sugar which had been present in the punch, from which the authors draw the conclusion that alcohol is more rapidly digested than sugar.

From these experiments the authors conclude that alcohol is absorbed by the veins, and not by the lacteals, and that, with the exception of the small quantity which escapes by the lungs, it is entirely oxidized into carbonic acid and water, either directly, or by passing through the intermediate stage of acetic acid.-Annales de Chimie et de Physique, December 1847.

12. Upon the Origin of the Granular Cell (Exudation Corpuscle, Henle; Inflammation Globule, Gluge). By M. REINHARDT. The author, in some former researches on the granular cell, came to the conclusion that all nucleated cells having albuminous contents, were capable, under certain circumstances, of becoming granular cells, whether they were originally normal constituents of the organism, or productions peculiar to the pathological condition. Having shown that this is the case in the products of inflammation, he now proceeds to demonstrate the same fact with regard to other cell formations, particularly in the membrana granulosa of the Graafian vesicles of the mammalia. The Graafian follicles, as is well known, are found in the ovary in great numbers, the great proportion of them being abortive, and, after a certain period of growth, diminishing and being absorbed. While the growth of the vesicles is proceeding, they are quite transparent and globular; the fluid which distends them is transparent, of a yellow colour, free of granules, and frequently coagulable. The membrana granulosa, at this stage, presents the appearance of a soft pellicle; microscopically examined, it consists of nucleated cells placed close together, and having a diameter, in most animals, of from 0004 to 0007""; their nucleus, which is from

0·003 to 0·005", appears decidedly granular. The cell membrane is transparent and structureless. The contents of the cells are sometimes a little turbid, from the presence of molecules, but are rendered clear by acetic acid, and also by caustic alkalies. Along with these cells are found other bodies, which are evidently a prior stage of their development. First, there appear small molecules soluble in caustic alkalies, sometimes very pale, sometimes more distinct and shining; then small granules varying from 0.0005 to 002", which have the same reactions as free cell-nuclei; they are sound, smooth, and shining, without nucleoli. When treated with acetic acid, they become flattened, and acquire a central depression like the nuclei of pus corpuscles. Next to these appear small cells, from 0·001 to 0003", which have one or sometimes two nuclei of the same appearance as the free nuclei above described. The contents of these cells are mostly transparent, but sometimes they appear to contain small molecules of proteine. The cell membrane is delicate and transparent. Between these cells and the above described granulated cells, every grade can be traced. Thus, there appear somewhat larger cells, whose nuclei are no longer round and homogeneous, but somewhat flattened and granular, and also further