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caudal stylets are found at a considerable distance from the posterior margin of the trunk; 

 they are comparatively large and nearly of a similar structure to those of the female, only 

 I have not been able to find any ordinary seta beside the one which is shaped like a joint. 



OVISACS. They are small (fig. 2 c), nearly round, frequently somewhat flattened, 

 with but few eggs, but then again as many as twenty-eight ovisacs may be found with one 

 female. The longest diameter of one of the ovisacs represented (containing eggs) is -42 mm. 

 The eggs of about medium size. 



LARVA. The specimens examined, of which the one partly represented in fig. 2i 

 had a total length of '23 mm., were pulled out of the egg-membranes, so the shape of their 

 body in a free state cannot be determined with absolute certainty, however, their cephalo- 

 thorax seems to be comparatively somewhat shorter and broader than that of the preceding 

 species, and to agree more with S. dispar. The larva is easily distinguished from all the 

 other species by having no processes whatever on its front, instead of which, however, we 

 find half its surface occupied by three pairs of transverse, partly curved, outwardly connected 

 lists. In many specimens, e. g. the one figured, the olfactory seta of the antennulae is 

 remarkably short, not half the length of the cephalothorax, whereas in other specimens I 

 have found it reaching to the natatory legs (this difference is inexplicable to me). Antennae 

 much as in the preceding species, except, indeed, that the broad basal part consists of two 

 pretty distinctly separated joints, the first of which is short; so the antenna is 4-jointed. 

 Maxillulse much as in S. decorata. First joint of the maxillae as in the preceding species, 

 second joint with some fine hairs on the ventral side of the distal end; third joint sometimes 

 as in S. decorata, but most frequently with three processes on the inner side, and then the 

 curved end of the joint itself is generally shorter than the most distal of the processes. 

 Abdomen as in S. decorata. 



POST-LARVAL DEVELOPMENT. Unknown. 



HABITAT. The marsupium of Eudorella emarginata (Kr.) from Denmark. In a 

 large material I have found altogether seven infested specimens. The following statistics 

 can be given. In one specimen were found: one shrunk female, three males and thirteen 

 mutually adhering ovisacs, most of them with eggs, some of them with Nauplii; in another 

 specimen occurred : one good-sized female, one male and twenty-two mutually adhering ovisacs, 

 a few of which contained developed larvae. In a third specimen the female and the ovisacs 

 together formed an oblong lump; the female, which was good- sized, was so closely surrounded 

 by the considerably flattened, mutually pretty firmly adhering ovisacs, that only a very small 

 part of it was visible on the side turning towards the ventral surface of the host; of 

 ovisacs I found twenty-eight, some of which contained eggs, most of them brood in different 

 stages, but in hardly any of them were the larvae ready to burst the egg-membrane; a single 

 male was attached to the outside of the lump. 



REMARKS. In the structure of the caudal stylets in both sexes, and in the frontal 

 area of the female, this parasite differs from all other species. 



20* 



