136 



as a rule, ends in one or two short and one longer setae, the latter of which, however, is 

 only half or scarcely half the length of the basal joint of the maxillipeds (sometimes there 

 are two about equally long setae at the end of the outer branch), and finally a rather short 

 seta on an angular process of the peduncle outside the outer branch. Tlie second pair of 

 legs comparatively pretty long, with a short outer branch at their base, ending in a shorter 

 seta, while the inner branch ends in sevei'al setae, the longest of which is distinctly longer 

 than the setae of the first pair of legs. The caudal stylets are lather small, with short setae. 

 — The frontal thread is between two tliirds of or the entire length of the whole body, 

 simple, ending in a thick disk. 



OVISACS. They are of medium size (fig. 3d), without great mutual difference (at 

 least if not containing young ones), for the most part shortly oval; the ovisac represented is 

 •47 mm. long and 39 mm. broad. The eggs of medium size, not very numerous. 



LAE,VA. I have found no free specimen, and the larvae which I pulled out of the 

 ovisacs were not sufficiently developed to allow of giving a description of them. 



POST-LARVAL DEVELOPMENT. Some pupse of both sexes have been found 

 (fig. 3i — 31), and their interesting development is described on p. 54 — 55. 



HABITAT. The marsupium of Frotomedeia fasciata Kr. from Denmark. In a 

 large material without specialised locality are found eleven infested specimens; a twelfth 

 one was taken by Dr. Joh. Petersen in the Kattegat at Stat. 403 (twelve fathoms). Only 

 seven of these twelve specimens have been very closely examined, but a statistic account of 

 four of them will be sufficient. In one specimen were found: the female repi'esented in 

 fig. 3 c, with a male adhering to its ventral surface, and six ovisacs partly glued together. 

 In another specimen were found: a good-sized female, a male and seven ovisacs, thus di- 

 stributed : three ovisacs were lying beside and in fi'ont of the female, the remaining four 

 and the male lying behind it; finally, a pupa was hinged to the base of the gill of the 

 liindmost leg but one. In a third specimen occurred: one good-sized female, five males, 

 three ovisacs and five pupae; four of the males and all the pupae were hinged to gills, to 

 marsupial plates or to the epimera of the second — sixth pair of legs. In a fourth spe- 

 cimen appeared the extremely large female represented in fig. 3a, one male and one pupa; 

 the female occupied the front half of the marsupium, whereas its hindmost half was occupied 

 by six of the host's eggs, containing young ones about half developed; in which the limbs 

 were very distinct. 



20. Sphaeronella Bonnieri n. sp. 



(PI. VI, fig. 4a-4d; pi. VII, fig. la— lb.) 



FEMALE. The specimen represented in fig. 4a — the largest one found — measures 

 ■97 mm. in length and •94 mm. in breadth. In the head and its organs of this species com- 

 pared with the preceding, I liave not been able to find any deviation which would seem 



