Gudger — Notes on Sorrn Beaufort, N. C, Fishes. 1 19 



ance of these gills this is taken in through the spiracles as Alcoek (1901 ) 

 conjectures for the congeneric Pteroplatea micrura of the Indian Ocean. 

 Indeed on July 17, while handling the just-dead, advanced embryos of 

 the butterfly ray, a considerable amount of flocculent material, i. e., 

 coagulated milk, was discharged from the months of two of them. These 

 two young rays, when taken from the uteri, had their pectorals rolled up 

 like those of the sting ray, but in reversed fashion, i. e., ventrally. 



One of the large females referred to in a preceding paragraph had the 

 tail gone from its point of junction with the ventrals. Calling the atten- 

 tion of my head fisherman to this, lie remarked that it was rare to find a 

 butterfly ray so mutilated. In this connection he added that in very 

 large and old specimens of this ray occasional ones were found to have 

 stings. In 1911 this statement was repeated by other fishermen, men 

 like the former, in whom I have confidence. I have examined for such 

 a spine nearly every large butterfly ray 1 have ever taken, but so far have 

 never found any indication of one. Its occurrence must be rare. On 

 this point Smith (1897) says "spine usually (always?) lacking." 



All of the females taken in 1910 had embryos in eacli uterus. The two 

 largest ones, .'52 inches wide by 19 long and 30 inches wide by 18J^ long, 

 had in addition their left ovaries only filled with eggs from 5-10 mm. in 

 diameter. These were taken July 16. From these facts the conclusion 

 may be arrived at that the butterfly ray may give birth to two sets of 

 young each season, and that if so the second set will probably be borne 

 in the left uterus only. However, this matter needs further investigation. 

 In the ovaries of these rays, as in those of Dasyatis say, the lumina were 

 tilled with an abundant yolky material which probably came from the 

 breaking down of some of the ova. In all these ovaries, however, there 

 were large eggs approaching maturity. 



In my Notes for 1900* the fact is recorded that the young of the cow- 

 nosed ray, Rhinoptera bonasus, come into the world rolled up like a piece 

 of paper, one pectoral inside, and one out. The young of the common 

 sting ray have the pectorals turned upward and rolled inward and down- 

 ward toward the median line, like two hands placed wrists together, 

 palms uppermost, ringers closed to touch palms. While in a preceding 

 paragraph it is noted that the young of the butterfly ray are born with 

 the pectorals held in reverse fashion, i. e., turned downward and rolled 

 inward. Hill ( 1862) has figured and described the young of the Jamaican 

 Cephaloptera massenoides, a ray probably near to Aodon hypostomus or 

 Mobula olfersi, with pectorals folded on the dorsal surface, one over- 

 lapping the other. Earlier, however, than any of these writers, Galard 

 de Terraube (17!)9)t described the young of a long-tailed ray of Guiana 

 (name not given) as coming into the world rolled up like waffles 

 ( gaufl'res ) , — like the young cow-nosed ray. It seems that these differences 

 find explanation in the supposition that the young rays in the uterus of 

 the mother are able to change the position of their pectorals just as the 

 young teleosts in the egg are able to shift their tails from right to left side 

 of the egg or vice versa. 



•Gudger, l*uo. 



■i-Tableau de < Sayenne ou de la < luiane Prancaise, pp. 131-2. 



