462 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [10] 



ent occurrence of an imperfect segment of triangular shape interjected 

 between two others which are but slightly irregular ; in other cases it 

 bas the appearance of two segments, one lying diagonally across the 

 other and the two, as it were, welded together. Measurements of the 

 head are not satisfactory on account of the extreme contractility of 

 that part. 



The following measurements were made from a mounted specimen 

 corresponding in position and appearance with Fig. 9 : 



Millimeters. 



From tip to tip of extended bothria 1. 48 



From apex of proboscis (retracted) to neck 0.96 



Bread tb of neck 0. 20 



Breadth of first segment 0. 20 



Length of first segment 0. 04 



Distance from head to first segment 1. 40 



Length of a mature segment 2. 60 



Breadth of a mature segment 0. 60 



Length of segment near posterior 1.20 



Breadth of segment near posterior 0. 50 



Lengtb of longest living strobile 108. 00 



Habitat added: Common Skate (Raia erinacea), spiral intestine. 

 Wood's Holl, Mass., August 25, 1884. 



Spongiobothriitm,* gen. nov. 



Body articulate, tseniaeform. Head separated from the body by a neck. 

 Bothria four, opposite, pediceled, broken up into locinio-crispate folds, 

 which arc transversely costate. [Inarmed; auxiliary acetabulum none 5 

 terminal papilla none. Genital apertures marginal. 



This genus combines many of the characters of Ucheneibothrium Van 

 Beneden and Phyllobothrium Van Beneden. It differs from the former 

 in the lacinise of the bothria and in the absence of a terminal haustel- 

 lum ; from the latter in having pediceled instead of sessile bothria? 

 and in the transverse costaj on the bothria. 



Spongiobothrium variabile, gen. et sp. nov. 



[riatell, Figs. 13-19.] 



Body articulate, tamircform. Head separated from the body by a 

 short neck, subquadrangular, tapering posteriorly, continuing at the 

 anterior angles into four bothria. The bothria are pediceled and on 

 their outer faces and borders are broken up into a number of delicate 

 frill-like laciniae, which are sometimes gathered into a more or less com- 

 pact mass of crisp, puckered, or purse-like folds (Fig. 15) and some- 

 times expanded into long, curved, auriculate,or leaf-like flaps (Fig. 16). 

 These are marked by transverse, parallel costse which originate from a 

 middle portion like the midrib of a leaf. There is no trace of either a 

 *I,7z6yyoS — a sponge or mop. 



