136 



ANATOMY AND PHYSIOLOGY OF 



the form of generation a,' it is entirely left 

 out of consideration that generation a pro- 

 duces (the so-called) generation b by a 

 process of gemmation ; whilst the process 

 by which generation b produces generation 

 is one of true generation. So generation 

 c developes d by gemmation, which resem- 

 bles B ; and d, by a true generative act, 

 produces e, which resembles a and c. This 

 distinction, although it may at first sight 

 appear merely verbal, will yet be found of 

 fundamental importance in the appreciation 

 of the trvie relations of these processes, and 

 of their resulting products. So, in the 

 Author's opinion, the application of the 

 term ' generation ' to the entire product of 

 the development of any germ originating 



in a generative act, whether that product 

 consist of a single individual, or of a suc- 

 cession, will be found much more appropri- "^ 

 ate, and more conducive to the end in view, 

 than the indiscriminate application of it to 

 each succession, whether produced by gem- 

 mation or by sexual re-union. It is of 

 great importance to the due comprehension 

 of certain phenomena of Reproduction, 

 which will come under consideration in the 

 Animal kingdom, that the relations of the 

 products of these two processes should be 

 rightly appreciated; and this appreciation 

 of them will, it is believed, be best gained 

 by a careful inquiry into the phenomena 

 of Reproduction in the Vegetable king- 

 dom." 



EXAMINATIONS RESUMED. 



GLAXDULAR APPARATUS. 



Q. Describe the structure of a glandular body. — A. 

 It consists of a collection of tubes, more or less convo- 

 luted, united by cellular substance into masses of a 

 rounded form, constituting a lobule ; each lobule has 

 a separate investment of membrane; and the whole 

 aggregate of lobules is furnished with a general mem- 

 branous envelope or capsule. Each gland presents a 

 complex arrangement of numerous arteries, veins, 

 nerves, and Ij-mphatics, and most of them are provided 

 with an excretory duct, which conducts the secretion 

 prepared in the gland. 



Q. What glands are supposed to be destitvite of a 

 secretory duct? — A. The pineal gland, thjToid, thy- 

 mus, and renal capsules. 



Q. AVhat function do most of the glands perform ? — 

 A. Their function is two-fold, namely, the separation 

 of some material fi-om the circvdating fluid, which 

 would otherwise prove injurious to the system, and the 

 elaboration of a product destined to renovate the tis- 

 sues. 



OF THE ABDOMEN. 



Q. How is the ca^•ity of the abdomen bounded? — 

 A. Anteriorly, by the diaphragm; posteriorly, by the 

 peh-is ; superiorly, by a portion of the vertebra ; infe- 

 riorly and laterally, by abdominal muscles. 



Q. Into how many regions is the abdomen divided ? 

 — A. Into nine, as follows : right and left hypochon- 

 driac; right and left lumbar; right and left iliac; epi- 

 gastric, umbilical, and liipogastric. 



PERITONEUM. 



Q. Why is the peritoneum called " serous mem- 



brane?" — A. In consequence of the serous or watery 

 fluid wth which its surface is constantly moistened. 



Q. What is the structure of serous membranes ? — 

 A. The same as that of the areolar tissue, ha\ing a 

 very smooth and glistening inner sm-face, which is 

 covered with a layer of cells ; constituting a distinct 

 tissue, termed epithelium. This is in contact with the 

 primary membrane, thus isolating it from the tissues 

 beneath. Sub-adjacent to tliis is a layer of condensed 

 areolar tissue, wliich constitutes the chief thickness of 

 the serous membrane, and confers upon it its strength 

 and elasticity; tliis gradually passes into that baser 

 variety, by which the membrane is attached to the part 

 it lines, and which is commonly known as the sub- 

 serous tissue. A fibrous tissue enters into the compo- 

 sition of the membrane itself, and its filaments inter- 

 lace in a beautiful network, wliich confers upon it 

 equal elasticity in every dii-ection. 



Q. What is the purpose of tins membrane ? — A. 

 To facilitate the movements of the contained organs, 

 by forming smooth surfaces which shall freely glide 

 over each other. 



ST01L\CH. 



Q. What effect does the gastric fluid have upon the 

 food ? — A. It is supposed to have the property of dis- 

 sohing the albuminous and gelatmous constituents of 

 the food. 



Q. What is the real solvent of the gastric fluid ? — 

 A. Either hych-ochleric, acetic, or lactic acid. 



Q. Is not the solvent action of the gastric fluid aided 

 by some mechanical means ? — A. Yes. By the move- 

 ments of the walls of the stomach, wloich ai-e produced 

 by the successive contractions and relaxations of their 



