Fishes of the Western North Atlantic 493 



Size. Some are born when less than 550 mm wide (see Study Material), but it 

 seems that others are not born until somewhat larger.'' Females may mature when 

 little more than 3V2 feet wide, for the state of the uterus of one 1,110 mm wide (about 

 44 in.) showed that she was gravid; no doubt she had expelled her young prematurely 

 at the time of capture.*' The claspers of a male about 45 inches wide (1,140 mm) 

 appeared to be fully developed. "» And "the width of adult specimens rarely exceeds 

 four feet."»» 



Developmental Stages. Embryos, when nearly ready for birth, closely resemble their 

 parents and lie with one pectoral rolled around the other."" Earlier stages have not been 

 described nor have we seen any. In the only reported case, a female contained one 

 embryo only. In gravid females, the walls of the uterus are clothed with the "charac- 

 teristic vascular villi. The uterine milk is greenish. "i«i 



Habits. The Lesser Devil Ray feeds chiefly on planktonic Crustacea and to a lesser 

 extent on small schooling fishes. The contents of the few stomachs examined consisted 

 of either small mysid-like shrimps or striped salt-water minnows {Fundulus majalis) 

 which are plentiful along the beaches of North Carolina where the observations were 

 made. "2 The method of feeding was observed long ago at Jamaica, where this Ray was 

 described as pushing its way through the so-called turtle grass; "it takes into its wide 

 mouth the congregated living things that are in its way," while "its head fins .... 

 direct the food to the mouth. ""^ When in pursuit of a school of minnows, they are 

 described as "rushing right up on the sand .... until their bodies were nearly half out 

 of water; but in an instant they were off and scattered out to sea.""* When swimming 

 quietly they keep their cephalic fins tightly curled so that they point forward like horns. 

 But when pursuing a school of minnows, the fins "open and, meeting below the mouth, 

 form a funnel, through which the 'minnows' are carried into the mouth. On the instant 

 that this rush is over these fins again close up tightly."i»5 



Those that reach the North Carolina Coast are described as travelling in schools; 

 they are capable of swimming at high speed and they often leap high above the surface. 

 They are said to utter a bell-like bark when captured,"' but it is not known whether 

 they make any sounds while in the water. 



Gravid females have been taken both in Jamaican waters and near Cape Lookout, 

 North Carolina, showing that they may produce young anywhere within their geographic 

 range. The male of a pair observed while mating "was above with back just showing 

 above the water and his wing-like pectorals curved upward .... while the female 



96. An embryo i6 inches wide has been reported (Hill, InteU. Observ., 2, 1S62: 167). 



97. RadclifFe, Bull. U.S. Bur. Fish., 34, 1916: 280. 98. Leigh-Sharpe, J. Morph., 42, 1936: 317, fig. 12. 

 99. Coles, Bull. Amer. Mus. nat. Hist., 35, 1916: 654. We find no definite record of a measured specimen wider than 



four feet. 



100. See Hill (Intell. Observ., 2, 1862: 176) for illustration of embryo with left-hand pectoral rolled around the right- 

 hand one. 



loi. Radcliffe, Bull. U.S. Bur. Fish., 34, 1916: 280. 



102. Ten stomachs examined (Coles, Bull. Amer. Mus. nat. Hist., 28, 1910: 242; Copeia, 32, 1916: 45-46; RadclifFe, 

 Bull. U.S. Bur. Fish., 34, 1916: 280). 



103. Hill, InteU. Observ., 2, 1862: 170. 104. Coles, BuU. Amer. Mus. nat. Hist., 28, 1910: 341. 

 105. Coles, Bull. Amer. Mus. nat. Hist., 35, 1916: 652. 106. Coles, Bull. Amer. Mus. nat. Hist., 28, 1910: 343. 



