476 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [24] 



acetabulum in this worm is therefore sufficient reason for not including 

 it in the genus Cylindrophorus. The almost invariable occurrence of 

 spines on the neck or body, or both, together with the shape of the 

 bothria and hooks, present so many points of resemblance to Wagener's 

 figures, from which Diesing created the generic name Cylindrophorus, 

 that I do not feel justified in adding a new generic term to the already 

 burdened nomenclature of Helminthology without at the same time 

 admitting Diesiug's Cylindrophorus in the probable synonymy of the 

 genus. 



The ovaries occupy nearly the posterior fourth of the proglottis. The 

 vagina extends, from its origin in the ovaries, as a sinuous duct along 

 the median line of the proglottis until it reaches the middle point, where 

 it turns nearly at right angles and opens in front of and immediately 

 adjoining the penis. The latter organ is retracted and lies coiled up in 

 the angle of the vagina, but seems to be connected with a convoluted 

 mass, which is situated centrally in the proglottis. A median tube can 

 be traced from near the anterior end of the proglottis to the angle of 

 the vagina and seems to lie parallel with that duct for some distance. 

 Its union with the latter could not be made out. The greater part of 

 the interior of the proglottis is filled with irregular granular masses, 

 each of which is composed of several irregular or disk-shaped pieces, 

 which are rather loosely joined together. 



In a specimen which had been subjected to double staining in green 

 and red analine colors, the ovaries in the base of the proglottis and 

 what appeared to be their continuation into a double row of coarse granu- 

 lar masses lying along each margin, had a strong affinity for the blue 

 staining. On the margins, outside of the coarse granular layer, a fine 

 granular layer, and outside of that a transparent, structureless, epi- 

 dermal layer, were differentiated. The vagina and anterio-median tube 

 were also slightly stained with the green. The interior compound gran- 

 ular masses, the penis, and the convoluted mass of tubes (vas deferens) 

 were unaffected by the green coloring matter. They were clearly differ- 

 entiated, though not deeply stained, by the red analine, nearly all the 

 red stain having disappeared when the specimen was washed in alcohol. 



Habitat. — Dusky Shark (Carcharias obscurus), in spiral intestine. 

 August, 188 1, Wood's Holl, Mass. 



Calliobothrium Yan Beneden. 



CalUobothrium verticillatum Rudolphi. 



[Plate IV, Figs. 1-8.] 



Onclwbothrium verticillatum Rud., Diesing, Syst. Helm., i, GOG. 

 CalUobothrium verticillatum Van Beneden, Dies., Revis. d. Ceph. Ab. Par., p. 



280-281. Van Beneden, in Mem. Acad. Belgique,xxv, 138 and 192, tab.xii. 

 Bothriocephalus verticillatus Rud., Synops., 142 and -1S4. Leuckart, Zool. 



Bruchst., i, 56, tab. ii, 41, fragm. Nitzsch., Ersch., and Grub., Encycl., 



xii, 99. Dnjardin, Hist. Nat. des Helminth., 621. Creplin, Troschel's 



Arch., 1849, i, 73. 



