774 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [56 



broad at base. They arc straight, with sharply recurved and hooke 

 extremities. 



I have not yet succeeded in making out the other genital organ 

 with entire certainty. The sections show near one of the lateral face 

 a number of irregular masses, which, from their striated appearanc 

 and absence of stained nuclei, I suspect to represent the convolute 

 vas defereus. Toward the interior of the segments these give plac 

 to irregular granular bodies from .02 to .Oi"* 11 in diameter, which fi 

 the interior of the segment around the muscular cirrus sheath. Thes 

 bodies evidently represent the spermatic capsules of the testes. I fin 

 no traces of even the beginning of female genitalia in these segment! 



Transverse sections of the head show that the loculi are formed by 

 dense layer of parallel radiating fibers, which is very sharply define 

 from the deeper tissue of the bothria. This layer is about .05 1 "" 1 thic 

 at the bottoms of the loculi, but is somewhat thinner at the edge: 

 It appears to consist of columnar epithelium. Where two locnli joii 

 this layer of radiating fibers in each rises to form the separating cost; 

 The transverse section of^a costa therefore shows it to be composed c 

 two layers which are confluent at the outer edge. This radiate fibrou 

 tissue contains a few scattered granules, which, although very smal 

 in several instances proved to be distinctly nucleated. The radiatiu 

 . fibers of the bothria themselves originate from a thin layer of fin 

 fibers, which in many places seems to have separated from the tissu 

 beneath, but which, in normal position, rests on a layer of coarse long 

 tudinal fibers in the center of the bothria. Towards the edges of tb 

 bothria the coarse longitudinal fibers disappear and the layer of radia 

 ting fibers is succeeded by the outer granular tissue of the head, ii 

 which there are a good many longitudinal fibers. 



Four principal vessels are cut by these cross-sections. Of these, tw< 

 lie near the center of the head and are .015 mm and .O2'" m in diametei 

 near the middle of the length of the head. The others are larger, ob 

 long, and are situated near the margins. Near the middle of the hea< 

 the inside diameters of one of the marginal tubes were .025 and .016" 

 the outside diameters .032 and .038'""'. These dimensions are some 

 what exaggerated since the sections were carried a little obliquel; 

 through the head. 



Transverse sections of the neck reveal the same alternation of mus 

 cular layers as noticed in the segment. The fascicles of the thick laye: 

 of longitudinal muscles are oblong in section and are disposed radially 

 around the central space. This layer is interrupted for a short distanc< 

 at the margins, where the granular central space is continuous with tin 

 granular layer, outside the fascicular layer. 



In some sections there are three, in others there appear to be four 

 vessels near the margins. Two of these are larger than the others 

 The outer one of these two, that is, the one nearer the margin, has 

 definite limiting wall, while the other is more irregular in outline ant 



