NO. 1123. PROCEEDINGS OF THE NATIOXAL MUSEVM. 797 



During life these embryos, when liberated from tbe blastocyst, showed 

 the structure with unusual clearness. The muscular retractor of the 

 proboscis was demonstrated (Plate III, fig. 12) and traced to its inser- 

 tion near the base of the contractile bulbs, and seen to be distinctly 

 fibrous (Plate III, fig. 13). Circular muscles seen in walls of contractile 

 bulbs and also in walls of proboscides. An irregular granular mass near 

 apex of head was probably tlie nerve ganglion. Two i^rincipal branches 

 led back from it, but could be traced for only a short distance. 



The surface of the bothria was densely covered with minute bristles. 



A granular ribbon with irregular outlines was seen through the 

 transparent walls of the extended proboscides (Plate III, fig. 32 (j) in 

 the living specimen. 



13. This singular specimen (Plate III, figs. 14, lo, 10) Avas found in a 

 bottle containing siJecimens of it*, lonr/icorne, from the spiral intestine 

 of the sand shark {Carcliarias Uttoralis), Woods Holl, Massachusetts, 

 August 12, 1887. No notes were made on the living specimen (No. 4703, 

 U.S.N.M.). Dimensions of alcoholic specimen: Length, 4 mm.; breadth 

 of head, 0.37; diameter of neck, 0.28; length of contractile bulbs, 0.04; 

 length of head and neck to base of bulbs, 0.94; length of largest hooks, 

 near base of proboscis, 0.04 ; length of small hooks, toward apex of pro- 

 boscis, 0.000. The body is vase-shaped and intimately attached to the 

 neck. Four elongated racemose clusters of oval or i)yriform bodies 

 extend from about the front end of the contractile bulbs nearly to 

 the posterior end of the body. The proboscides were retracted, and 

 the character of the hooks could not be made out satisfactorily. The 

 proboscis appears to be swollen at the base. Several large stout hooks, 

 and some straightish ones, at the base of the proboscis ; beyond the base 

 the hooks are much smaller. 



14. Figs. 17, 18, 19, Plate III, are sketches of a larval Bhi/nchohothrium 

 from a cyst on the liver of the bluefish {Pomatomus saltatrix), collected 

 at Woods Holl, Massachusetts, September, 1884. 



This specimen (Xo. 4771, U.S.N.M.) was associated with specimen 

 of B. speciosum, but was much smaller than specimens of that species 

 of corresponding degree of development. The length of the entire 

 specimen (fig. 17) was about 11 mm.; the breadth of a bothrium, 0.5<>. 



IV. 



In this section are included notices of the occurrence of encysted 

 Rhynehobothria whose specific identity could not be determined even 

 approximately, usually on account either of the immature condition of 

 the embryo, or because of the degeneration of the tissues of the blas- 

 tocyst itself. 



15. Cyst from peritoneum of common flounder {Paralichthys denlatus), 

 Woods Holl, Massachusetts, August, 1884. 



These contained small scoleces of Bhynchobothrium; proboscides 

 retracted, hooks of three or more kinds, their arrangement not clearly 

 made out, but their shape and size point to E. bulbifer. 



