424 Mr, A. Alcock on 



§ 5. The Nature of the Secretion. 



The amount of secretion available for examination was so 

 small — only about a fluid drachm, including debris of tropho- 

 neniata — that no satisfactory results have been obtained. 



The capture was at a distance from the ship^ and to guard 

 against putrefaction the secretion was removed and bottled 

 and covered with strong (rectified) spirit. By the action of 

 the spirit it was at once coagulated. 



When fresh it looked like custard, or, rather, like thin pus ; 

 it was viscid, had a sticky greasy feel, and a heavy sweetish 

 meaty smell. Prolonged heat at 21^° Fahr. leaves a trans- 

 lucent horny cake (albumin). Fresh Fehling's solution gave 

 no reaction (no sugar), but the quantity tested was so small 

 that the inference must be quite uncertain. A greasy white 

 film (probably fat) was left wherever the secretion touched 

 the bottle. 



A portion of the clot macerated in water, stained in car- 

 mine, and examined in glycerine, shows an abundance of 

 formed elements. Besides epithelium, which may perhaps 

 be adventitious, there are to be seen crowds of round granular 

 cells of a uniform diameter of about -joou of an inch. Of 

 these some, though quite transparent, possess no nucleus at 

 all, fewer others have two or more nuclei, while the great 

 majority have a single small excentric nucleus. There are 

 also to be observed free nuclei. 



In the Mahiinadi s})ecimcn the secretion, which was abun- 

 dant glairy and turbid, was tested only for albumin, and 

 coagulated in lumps when heated. 



The secretion thus seems to vary ; and it may be men- 

 tioned that in Fterophitcea micrura — a viviparous fish allied 

 to the Trygons, and one which carries its young in the same 

 way — the secretion changes with the advance of gestation. 



As to the nature of the secretion, then, all that can at 

 present be predicated is that it is very rich in albumin and 

 that it contains a remarkably large proportion of corpuscles 

 and nuclei. 



§ 6. The Foetus ofTvygow Blcekeri. 



On removing the foetus we are first attracted by the large 

 size of the spiracles, which arc full of the creamy uterine 

 secretion. 



It may perhaps be of advantage to recall the fact that the 

 spiracles are the first pair of branchial cKfts, which, in many 



