1891.] Uterine Villiform Papillae of Pteroplatsea micrura. 363 



idth mammalian physiology, has come to connote a structure which 

 ssentially absorbs nutriment, we propose to term the villiform struc- 

 tures of the uterine mucous membrane in Selachians, which essen- 

 tially secrete nutriment, trophonemata ; and by this name they will 

 i referred to in the descriptive portion of this paper. 



2. Recent Observations on the Uterine Villi of some Indian Rays. 



In the ' Journal of the Asiatic Society of Bengal,' vol. 59, Part II, 

 , 51, the second-named contributor of this paper described some 

 jbservations on the uteri and the gestation of Try g on bleekeri and 

 [yliobatis nieuhofii, which it is necessary here to briefly recapitulate. 

 In a large female of Trygon bleekeri, taken on the 15th December, 

 1888, in the Mahanaddi estuary, the distal end of the right oviduct 

 ras found to be enormously dilated, and to contain in its cavity a 

 lly-developed male foetus with a disk llf inches long and 10| 

 iches broad. The folded foetus lay free in the uterine cavity, quite 

 lestitute of membranous covering, without any structural con- 

 lexion with the mother, and without any vestige of external yolk- 

 The uterine mucous membrane, which was a vivid vascular 

 rlet, such as in Fishes is usually seen in the gill-laminae only, was 

 overed with an abundant highly-albuminous fluid, secreted by a 

 rowded layer of glandular filamentous villi which formed the inner 

 mfc; and it was inferred that this secretion was a uterine milk 

 elaborated for the nourishment of the embryo. In the absence of any 

 ecial absorbent organs, and because the embryo was so folded that 

 ly supposed " absorbent function " of the skin would have been as 

 inch as possible limited, it was further inferred that the " milk " 

 ras taken in by the embryo by the mouth!; though unfortunately 

 the foetal stomach was not examined until post-mortem changes were 

 Ivanced. It may be mentioned that the foetus did not possess 

 inchial filaments. 



Again, in Myliobatis nieuhofii, the structure of the uterine glands has 

 een made out, but we have had no opportunity of ascertaining their 

 slation to the egg or to the embryo. In an adult female, taken off 

 ae Grodavari Delta on the 31st March, 1889, the left ovary was found 

 be full of enlarged ova, while the distal end of the oviduct formed 

 globular swelling with thick, muscular walls, and a mucous mem- 

 rane thickly beset with long foliaceous villi. The entire surface of 

 le mucous membrane, both villous and inter-villous, was found to 

 Dnsist of a close-set aggregation of tubular glands, most of which 

 rere simple follicles resembling the Lieberkuhniau follicles of human 

 atomy, though at the periphery of a villus they are commonly 

 Jmose. 

 We have now, in the case of Pteroplatcea micrura, discovered 



