123 
OVISACS. They are of middle size; those hitherto found are somewhat irregular 
trom pressure, oblong (fig. 2a), the longest ‘69mm. long. The eggs large, not numerous. 
LARVA and POST-LARVAL DEVELOPMENT. Unknown. 
HABITAT. The marsupium of Astyra abyssi Boeck from Finmarken (Norway). 
In one specimen were found: the female mentioned, with the two ovisacs glued together and 
adhering to its foremost part, and a third one glued to its ventral surface, besides two males, 
one of which was fastened by the frontal thread shown in the drawing. In another specimen 
were found only four ovisacs, and these were discovered in examining some specimens of 
the above-mentioned Amphipod kindly offered to our Museum by Prof. G. O. Sars, upon which 
on my applying to him, he lent me his whole material for investigation, and [ discovered 
the specimen which supplied me with both sexes of the parasite. 
REMARKS. The description of the female is, unfortunately, very defective on 
account of the loss of the head. The male is exceedingly characteristic owing to the 
unique development of the terminal sete of its trunk-legs and caudal stylets. 
13. Sphzronella Argisse n. sp. 
(PLIV, fig. 3a—3n). 
FEMALE. The only adult specimen (fig. 3a) was somewhat shrunk and rendered 
crooked by pressure; its length was °85mm.; a small, recently hatched specimen represented 
in fig. 3c (enlarged on the same scale as fig. 3a) and strongly magnified in fig. 3d, is crooked 
and empty; its length is 15mm.. The head is small and well defined. The frontal margin 
is naked. The antennule have moderately long terminal sete. The antenne are 3-jointed, 
their terminal seta quite as long as the last joint. The mouth-border of medium breadth. 
The maxillule with additional branch. The maxilla smooth. The maxillipeds slender, 
their basal joint naked, the following three joints distinctly separated, the terminal joint 
pointed. The sub-median skeleton has narrow longitudinal lists inside the maxillz and no real 
transverse list at the median line behind the base of the maxillipeds; it is naked all over. 
The lateral margin of the head provided with rather short and fine hairs. The trunk quite 
naked; the trunk-legs well developed in the young ones, and probably also present in the 
adults. The genital area (fig. 3f) broader than the head (fig. 3a), somewhat broader than 
long; the solid chitine forms a semi-circle which opens towards the front; it is very broad 
posteriorly and decreases gradually in breadth; its two extremities form irregular lobes 
with inward curving points; the posterior margin is semicircular. The genital apertures 
oblique, the distance between them of medium length (in fig. 3f they are wide open and 
a spermatophore is attached to the entrance of one of the receptacula seminis). The caudal 
stylets are small but well developed and situated close together on the firm chitine imme- 
diately behind the genital apertures. The whole genital area is naked (the young one 
represented in fig. 3d has no genital area yet). 
16° 
