71 



genus, but built on the very same type. Posterior maxillipeds large and 

 massive, forming, as in Botryllophilus, the chief attaching organs. The 4 an- 

 terior pairs of legs very imperfectly developed, outer ramus eultriform, with 

 6 strong spines outside, inner ramus rather smaller and scarcely lamelliform, 

 being narrowed distally, and only provided with a restricted number of setae 

 at the tip. Last pair of legs forming 2 broadly oval lamellae encompassing 

 the body like a mantle, and extending nearly to the middle of the tail, each 

 lamella provided at the end below with a small bristle. Ovisac oval, flattened, 

 and extending almost to the end of the tail. 



Colour whitish gray. 



Length of adult female 1.80 mm. 



Male unknown. 



Remarks. The above-described form cannot be confounded with any of 

 the other members of the present family. From the species of the genus 

 Botryllophilus it is at once distinguished by the very different appearance of 

 the transformed last pair of legs, in which respect it more resembles the form 

 next to be described. 



Occurrence. A few female specimens only of this peculiar form have as 



"yet come under my notice. They were taken at Risor, south coast of Norway, 



and, as far as I remember it, from the branchial cavity of Phallusia obliqna. 



Gen. 14. Schizoproctus, Aurivillius, 1885. 



Generic Characters. Body of female fusiform in shape, with thin and 

 soft integuments and the segments only indicated by slight constrictions; that 

 of male more distinctly segmented and of extremely small size, as compared 

 with the female, to the ventral face of which it is found attached. Tail appa- 

 rently composed of 5 segments, and not very sharply marked off from the 

 trunk. Caudal rami small, curving outside, and minutely clawed at the end. 

 Antennae and oral parts built on the same type as in the 2 preceding genera, 

 but on the whole less fully developed. The 4 anterior pairs of legs very 

 small, with the rami uniarticulate and nearly of equal structure, both forming 

 small triangular pieces armed outside with short spines. Last pair of legs 

 (in female), as in Pteropygus, transformed to broad lamellae extending on each 

 side along the base of the tail and separated dorsally by a deep and narrow 

 cleft. Ovisac not yet observed. 



Remarks. This genus, established by Aurivillius, is evidently referable 

 to the same family as the 2 preceding genera, though the outward appearance 



