181 



OVISACS. They are mentioned in the description of the genus. In pi. XI, fig. 3 b 

 and fig. 3 c are drawn on the same scale of enlargement, thereby illustrating the relative 

 size etc. of the ovisacs. The largest of the ovisacs, represented in fig. 3 d, is - 90 mm. in 

 length and contains larvae, of which only six are drawn. 



LARVA. Full-grown larvae prepared out of an ovisac agree closely with those of 

 the following species; the only difference I have been able to find is, that the inner side 

 of the terminal joint of the maxillipeds is smooth in this species and spinous in the following 

 one. As for the rest, the reader is referred to the description of the next species. 



POST-LARVAL DEVELOPMENT. The stages found are described in detail 

 above on p. 61 — 63. 



HABITAT. The marsupium of Erythrops serratus Q. 0. Sars and Parerythrops 

 obesus Gr. O. S., and a female together with the following species in the marsupium of 

 Erythrops abyssorum G. 0. S. ; all from Norway. The following special data can be given. 

 In a specimen of Parer. obesus without special locality, one large female was found attached 

 to the inner side of the hindmost right marsupial plate near its base; it carried fifteen 

 ovisacs, one of which was empty; and two males appeared together with it. In an Er. 

 serratus (with two specimens of Aspidoecia) without special locality, occurred: an almost 

 empty female (with twenty-one spermatophores), carrying fourteen ovisacs of widely differing 

 sizes, one of them half emptied of young ones, another quite empty, and to the latter were 

 attached six males, one of which had four spermatophores fixed to the ventral side of its 

 trunk; further: an empty, partly destroyed skin of a seventh male, another male (the eighth) 

 fixed by a frontal thread, and a larva about to become a pupa. In another Er. serratus, 

 the locality of which was not specified, was discovered one large female (type specimen of 

 fig. 3 b) attached by its head to the basal part of a marsupial plate and carrying thirteen 

 ovisacs (six and seven), and together with it a half-grown female and a female in the 

 stage represented in fig. 1 d, each fixed to a separate marsupial plate by a dorsal thread. 

 In one specimen of Er. serratus (with at least one Aspidoecia), from Kvalo, a part of the 

 contents of the marsupium was washed away, but still three adult females, all with ovisacs, 

 and one male were found; in a specimen of the same species from Sunde, the marsupium 

 contained only one female with two ovisacs. Another specimen of the same species from 

 Sunde was highly interesting. Its marsupium contained, to begin with, the bulk represented 

 in fig. 3 a, the greater part of which consisted of a rather shrivelled female with seventeen 

 ovisacs, some of which contained eggs, others Nauplii or pretty old larvae, two were nearly 

 emptied of larvae, and one of the ovisacs was three-lobed, the majority of the others more 

 or less distinctly pyriform. The bulk was placed as follows: the part of it which is upper- 

 most in the drawing, was foremost in the marsupium, the part of it which turned towards 

 the abdomen of the host, was flat, but the opposite, ventral side strongly arched, as shown 

 in the illustration. This bulk contained, moreover, two males, the pupa fastened by a dorsal 

 thread and drawn in fig. 1 c, and a very small pupa, like the one represented in fig. 3 i. 



