139 



Remarks. This genus was established as early as the year 1851 by the 

 English naturalist Dalyell, to include a peculiar parasite found by him on a species 

 of brittle-stars. The systematic position of the genus has long remained very 

 uncertain ; but Giesbrecht clearly pointed out its near relationship to the siphono- 

 stomous Cyclopoidae (Asterocheridae) and particularly to the genus Parartotrogus 

 of Scott, I also fully agree with Giesbrecht, that the genus Caligidmm of Glaus 

 ought to be regarded as a synonym, being founded on adult males belonging 

 to this genus. 



76. Cancerilla tubulata, Dalyell. 



(PL LXXX). 



Cancerilla tubulata, Dalyell, The powers of the Creator, Vol. 1, p. 233, PI. LXII, figs. 15. 

 Syn: Caligidium vagabundum, Glaus, (adult male). 



Specific Characters. Female. Body very short and stout, almost cordi- 

 form in shape, with the anterior division greatly inflated, transversely ellipsoid 

 in outline, the width considerably exceeding the length. Cephalic segment occu- 

 pying by far the greater part of the body, free edges strongly curved and minutely 

 hairy in their anterior part, front very slightly produced. The succeeding segment 

 with the epimeral parts less distinctly defined, forming part of the hind boundary 

 of the anterior division; the remaining trunk-segments imperfectly developed and 

 only visible as narrow stripes. Tail very short, with the genital segment 

 exceedingly dilated, being nearly 3 times as broad as it is long, and projecting 

 behind on each side in an angular corner; anal segment larger than the pre- 

 ceding segment, and somewhat contracted distally. Caudal rami comparatively 

 small and rather far apart, apical setae short, the inner mediate one being, as 

 usual, the longest. Anterior antennae comparatively small and composed of only 

 6 joints clothed with short curved setae; 1st joint much the largest and rather 

 broad; terminal joint about the length of the 2 preceding ones combined, and 

 carrying near the end a comparatively small aesthetask in addition to the setae. 

 Posterior antennae very strong and highly chitinized; 1st joint rather short, the 

 2 succeeding ones of about equal size, terminal joint somewhat shorter, but con- 

 spicuously widening distally, apical claw exceedingly strong and curved. Maxillae 

 with the terminal lobe oblong in form and provided with 3 spreading non-ciliated 

 setae of moderate length and accompanied by a small bristle. Both pairs of 

 maxillipeds short and stout, with the dactyli not much produced, but rather 

 coarse. 1st pair of legs consisting each of a thickish basal part carrying outside 

 a small bristle, and 2 uniarticulate rami, the outer one lamelliform and edged 

 with 6 comparatively short simple setae, one inside, 2 at the tip, and 3 outside ; 



