NO. 1816 STORY OF THE DHVIL-FlSIi — GILL 



173 



with considerable knowledge of ichthyology, Swinburne Ward, once 

 the Civil Commissioner of the Seychelles Islands, after an account 

 of the capture of a Devil-fish which "ten men could not haul" up on 

 the beach, concluded with the affirmation that "she was full of eggs." 

 The idea might be (and has been) derived that this may have been 

 a case of oviparity or multiparity, but the eggs (if they were such) 

 were possibly the reserve stock left perhaps after the birth of a 

 young one. The statement is in great need of confirmation. 



Mitchill, in 1823, tells that a "female that was struggling after 

 having been w^ounded brought forth in her agony a living young 

 one, as Captain Potter related, and Mr. Patchen, while he showed 

 [Mitchill] the orifices through which sucking is probably performed, 

 declared that on dissection mammary organs were found, which dis- 

 charged as much as a pailful of milk." This at first incomprehen- 

 sible and incredible statement may be reconciled with facts when we 

 recall the mode of nutrition of the embryo among the Sting-rays, 

 described by Alcock. It was the honest statement of an inex- 

 perienced observer who misinterpreted facts. 



A remarkable provision among the Sting-rays for the nutrition of 

 the embryo within the body of the mother has been made known by 

 A. Alcock, on whose description, published in 1902, we may draw.^ 



It is by means of a secretion which is regarded as "analogous to 

 milk" that the embryo is for some time fed. The mucous membrane 

 of the oviduct is "shaggy, with vascular filaments [named trophone- 

 inata\ dripping with milk" or rather a milk-like fluid, and on micro- 

 scopic examination it was found that "each filament was provided 

 with superficial muscles whose contraction must serve to squeeze the 

 milk out. Some such mechanism is undoubtedly necessary, seeing 

 that the young one has no power of extracting the secretion for 

 itself. On examination of the young one, the mother's milk was 

 found inside the modified first pair of gill-clefts or spiracles (the 

 other gill-clefts being tightly closed), and also in large clots within 

 the spiral valve of the intestine, so that there can be no doubt that 

 in these viviparous Rays the unborn young ones may be said to 



^Alcock (A.). A Naturalist in Indian Seas [etc.], London, 1902, pp. 210, 

 71, 159. See, also, Observations on the Gestation of some Indian Sharks and 

 Rays. Journ. Asiat. Soc. Bengal, 59, pt. 2, 1890, pp. 51-56, pi. i ; On the Uterine 

 Villiform Papillae of Pteroplatea micrura, [etc.] Proc. Roy. Soc., 49, 1891, 

 pp. 359-367, pis. 7, 8; Further observations on the Gestation of Indian Rays; 

 [etc.] ; Proc. Roy. Soc, 50, 1891, pp. 202-209. On Utero-gestation in Trygon 

 hleekcri. Ann. Mag. Nat. Hist., (6), 9, pp. 417-427, pi. 19, 1892; Some Obser- 

 vations on the Embryonic History of Pteroplataa micrura. Ann. Mag. Nat. 

 Hist, (6), 10, pp. 1-8, pi. 4, 1892. 



