Gudge 1 ) — Notes on Some Beaufort, A r . C, Fishes. 147 



17, I7 1 .., is linn, in diameter respectively; the uterus on the same side 

 was greatly swollen, and shaggy with villi. Two others had the left 

 generative organs as above, although the eggs in the ovary were not quite 

 so large, measuring from !*_' to 15 mm. only. 



In no right ovary did the writer, in L911, find any large or even distinct 

 e>_ r L. r s, and in no lish did he find a right uterus functional. In this con- 

 nection it is pertinent to note that Haswell ( L888) states that in TJrolophux 

 testaa us the left oviduct only is functional. Alcock hears like testimony of 

 Trygon bleekeri ( 1892); " . . . in all the pregnant rays that I have since 

 dissected, where only one oviduct is pregnant it is always the left." 



From this data the following conclusions may be drawn. First, that 

 as a rule the left ovary and left uterus only of Dasyatis say are functional. 

 Secondly, that as the eggs ripen the uterus enlarges and becomes villous 

 to receive them. Thirdly, that this ray may give birth to a second set of 

 young each season. 



During the season of 191 1 the writer dissected a number of sting rays 

 to determine their food. In all specimens in which digestion had not 

 gone too far, this was found to consist of annelid worms of two kinds. 

 The first of a small-sized red worm found everywhere. The other of a 

 splendid large green worm. These rays are bottom feeders. Beaufort 

 harbor and the surrounding waters are filled with hundreds of acres of 

 sand and mud tiats in which live millions of tubiculous worms. These 

 thrust out their heads from the mouths of their tubes as the flood tide 

 covers the sand flats and at this time the rays come in over the shoals to 

 feed. 



The following incident may be related as showing how early the defen- 

 sive instinct manifests itself in this fish. On June 30, 1911, there was 

 taken in a haul of the seine a young female ray 6% inches wide, 6)^ long 

 to end of ventrals, and 12 inches to the end of the tail. This was probably 

 not more than a week, possibly not more than 2 or 3 days old. When 

 first picked up it lashed out with its tail and struck the point of its sting 

 in the writer's thumb, whereupon it was dropped into the boat. In 

 order to ascertain whether this was a purposed action or accidental, it 

 was again picked up, whereupon it again lashed out savagely with its tail. 

 It is probable that one taken from the uterus at the time of parturition 

 would do the same thing. 



During 11)11 there was taken by the writer a number of sting rays 

 whose caudal appendages had suffered abbreviation. Among them was 

 the young one above referred to. In addition 3 good-sized ones were 

 taken which were tailless. A 12-inch wide female had the tail completely 

 gone. An 18^-inch male had a stump one inch long. Lastly a 20-inch 

 male had a 2-inch stump. For a possible explanation of how this con- 

 dition in these rays has come about, the reader is referred to a previous 

 paper by the writer (Gudger, 1907), in which it is shown that sting rays 

 form no inconsiderable part of the food of the hammer-head shark, Sphyrna 

 zygitna. It may be conjectured that a hammer-head had been chasing 

 these rays. They lashed out with their tails and fixed their spines in its 

 head or jaws, whereupon the shark incontinently bit the tails off. 



