286 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



specimens on account of the enormously distended oterus, 

 those of the vitellaria can be seen in some specimens. They 

 are represented in fig. 2, PL III., but in some cases extend 

 further back than is shown. The eggs are oval, opercu- 

 lated, and without filaments. The longitudinal diameter 

 is OOSTmm., and the transverse is 0*024mm. 



The armature of the skin is very peculiar. It con- 

 sists, not of pointed spines, as in most trematodes, but of 

 scales set deeply in the skin, and with only the margins 

 protruding. Fig. 3 represents the armature of the 

 anterior part of the body, and shows the general size and 

 arrangement of the scales. There are, in addition, a 

 series of true backwardly hooked spines round the head 

 and on the margin of the anterior sucker : these rapidly 

 pass into the ordinary scales, which are distributed very 

 uniformly over the remainder of the body. Fig. 6 is 

 an oblique view of the surface of the skin in a very 

 obliquely cut transverse section, and shows the fish-like 

 overlapping of the scales in some parts of the body. Of 

 course, this overlapping will depend on the degree of con- 

 traction of the part examined. Fig. 5 represents part 

 of the skin as seen in a transverse section of the body, and 

 shows the scales cut in section. Fig. 4 is part of a 

 longitudinal section, and shows part of one row of scales 

 in surface view. 



Gasterostomum. sp. 



A " Bucephalus " cercaria form was found by Mr. W. 

 Tattersall, B„Sc, a former student of the Zoology Depart- 

 ment at Liverpool University, while dissecting Cardinal 

 edule. Mr. TattersaLTs notes say: — "Found in long, 

 narrow, tapering, and winding sporocysts in the region of 

 the liver and genital organs, and buried in these organs." 



All Gasterostoma appear to possess the " Bucepha- 



