866 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [148] 



lar in outline. The diameter of the granular or nuclear masses range 

 from .02 to .027 ram , that of the entire ovum from .03 to .05 mm . In 

 case, in a stained segment, there were observed amoug these grauula 

 masses with the transparent envelope a small cluster of amber-colorec 

 collapsed shells of ova about .036 and .022 mm in the two diameters. 



The cirrus was invagiuated in every case, but could be plainly seei 

 through the walls of the segment when the latter were rendered trans 

 parent in glycerine. The retracted cirrus is pyriform in shape, th< 

 inner end is the larger, directed anteriorly and a little toward one of the 

 lateral sides. It is very thickly beset with fine bristles. It measurec 

 .094 mm in length, and .05 mm in diameter, narrowing to ,02 mm near 

 external aperture. The external opening of the cirrus is near 

 margin, about the middle of the segment. In the posterior mature 

 ments, which were apparently slightly distorted, the genital apertun) 

 was situated from the margin. a distance equal to one-fourth the breadtl 

 of the segments. 



The ovaries are elongated, glandular, paired organs lying near thJ 

 posterior end of the segment, one on each side of the median line. ThJ 

 vagina appears to open beside the cirrus on its posterior side. ThiJ 

 fact, however, requires further verification. In segments which prc 

 cede the mature ova bearing segments the retracted cirrus was 

 to lie nearly transverse to the axis, inclined a little forward at the inue| 

 end, and equal in length to about three-fifths of the segments. 



The testes are represented by a few globular or oval bodies 

 along the middle line from the front end of the ovaries to the anteriol 

 end of the segment. These range iu diameter from .055 mm in sotn 

 specimens to over .08 mra iu others. One of the largest of these oval U 

 tides measured .086 and .047 mm in its two diameters. In those segment 

 in which the testes are best developed the ovaries are scarcely at all de 

 veloped. Furthermore, the transition from segments with large testi 

 cles and incipient ovaries, to those in which the interior is completely 

 filled with ova, is quite abrupt. 



The exceeding sraallness of this anomalous worm has doubtless cause* 

 it to be overlooked heretofore, while the extreme variability of the heac 

 might easily lead collectors to regard it as simply fragmental remain 

 of other and larger cestods with which the sting ray abounds. 



