36 PROCEEDINGS OF THE NATIONAL MUSEUM vol.88 



were massed in front of the ventral sucker, thus hiding much of the 

 vitellaria. The follicles of the vitellaria are rounded masses about 

 0.03 mm. in diameter, about 10 counted on the right side and 16 on 

 the left. On the right side they extend in a single row for a distance 

 of about 0.5 mm. ; on the left side they extend from the anterior edge of 

 the first testis forward in an irregidar double row, partly concealed 

 by ova, for a distance of about 0.06 mm. The ovary lay a little way in 

 front of the first testis to the right of the median line. Tlie testes 

 were nearly circular in outline, one following the other and about 

 0.4 mm. from the posterior end. 



Six (U.S.N.M. No. 8184), collected November 20, 1912, from barn- 

 door skate. 



Measurements in formalin: Length, 2.66 mm.; diameter of circle 

 of papillae, 0.15 mm.; maximum diameter of body, 0.28 mm.; about 

 20 short, conical papillae in anterior circle; ova, pointed at one end, 

 0.023 by 0.013 mm. The specimens in balsam are not in good condi- 

 tion. It was found that unless especial precautions were taken these 

 gasterostomes, which had been preserved in formalin, shriveled badly 

 when tiansferred from absolute alcohol to the clearing fluid. 



NANNOENTERUM GORGON (Linton) 



Plate 19, Figures 254r-256 



G aster ostomum gorgon Linton, Bull. U. S. Bur. Fish., vol. 24, p. 364, figs. 240- 

 242, 1905. 



The shape of the body is somewhat variable, but in most of the 

 specimens of the collection there is not much difference in the breadth 

 for the greater part of the length ; covered anteriorly wdth dense, low, 

 flat, rounded spines. Anterior sucker relatively large, surrounded 

 by about 20 tentacles, which, when extended are slender-pointed. 

 Ventral sucker behind middle of length. In one specimen, 2.66 mm. 

 long, the ventral sucker was 1.68 mm. from the anterior end; in 

 another, 2.9 mm. long, the ventral sucker was 1.57 mm. from the 

 anterior end. The intestinal cecum extends anteriorly from the ven- 

 tral sucker. The cirrus pouch may extend forward so as to overlap 

 the second testis. The testes lie on the right side, one following the 

 other, usually with a short interval betw^een them. The ovary usu- 

 ally lies on a level with the ventral sucker, and a short distance in 

 front of the first testis. The vitellaria are laterally placed, about 32 

 follicles in all, the anteriors of which are at about the anterior fourth, 

 or fifth, of the body length, and the posteriors but little if any back 

 of the ventral sucker. In one specimen four follicles on one side lay 

 back of the ventral sucker, the most posterior of them on a level with 

 the posterior edge of the ovary. There were 17 follicles on that side, 



