[137] NOTES ON ENTOZOA OF MARINE FISHES. 855 



I take the following descriptive paragraph from notes made at the 

 time of collecting : Bothria elongated in two lateral pairs, the bothria 

 constituting a single pair united at the apex, each with an irregularly 

 hollowed face and posterior bluntly rounded edges reflexed from the 

 neck. Anterior part of head projecting about 0.1 mm in front of the 

 bases of the proboscides, the latter shorter than the bothria. Neck 

 short, tumid, constricted behind the short contractile bulbs and con- 

 tinued posteriorly into a collar which surrounds the anterior part of the 

 body. The body is joined to the neck at the base of the bulbs. Fine 

 transverse lines begin at once behind the collar. The first segments 

 are broader than long. They increase in length rapidly and at a dis- 

 tance of 8 mm from the head are more then twice as long as broad. The 

 posterior mature segments are somewhat irregular in outline and tumid 

 in the middle. When placed in water the ripe segments are apt to 

 burst at the middle of a lateral face, by means of a rapid papillary 

 swelling from which the eggs escape. Under the compressor the di- 

 viding line between the ripe segments is indistinct. 



The spheroidal ova measure about 0.019 and 0.014 mm in the two diam- 

 eters. Some are nearly spherical and 0.019 mm in diameter. 



The epidermis of one specimen exhibited a tendency to slough off 

 after lying for a short time in sea-water. In some specimens, after 

 having been placed in sea-water, it was observed that the mature seg- 

 ments had curved towards one of the lateral faces, burst about the 

 middle, and discharged ova in such quantity as to leave a milky white 

 patch at the bottom of the dish. 



When alcoholic specimens were highly magnified the apex of the 

 head and the edges of the bothria are seen to be densely covered with 

 minute hair-like bristles, which are a little longer than the hooklets of 

 the proboscis. These bristles belong to the epidermis, are easily rubbed 

 off, can be seen only with a high magnifying power and hence may be 

 easily overlooked. 



In the mature segments the nearly spherical ova lie in scattered 

 masses. These small aggregations are probably what remain of the 

 ova, the greater part having escaped through the lateral aperture. 

 The cirrus emerges near or a little in front of the middle point of the 

 margin, thus differing from T.robustum, in which the cirrus opens near 

 the anterior margin. 



This species has many characters in common with T. infulatum (As- 

 pidorhynchus infulatus Molin). 



39. Tetrarhynchus robustum, sp. nov. 



[Plate xiv, Figs. 7-9.] 



Head bluntly rounded in front. Bothria four, oblong, hollowed out 

 on the face, with flexible borders, distinctly arranged in lateral pairs, 

 the bothria in each pair approximating at their fore posterior edges. 

 Neck variable, usually cylindrical, broader than anterior part of body, 



