72 



dindrmn Costa infested with a species of Splxrronplla [S. cliadrma Giard and Bonnier, without 

 description) and two other specimens of the same Amphipod with Podascon Bella Vallei Giard 

 and Bonnier. Of Decapoda theie have only heeii found as yet Choniostoniatidse on Hippohjte 

 Gaimardii M.-Edw. and on i/?>y). polaris (Sab.); both these species, we know, are not 

 unfrequently infested, either with Hcmimilirns nhdomhudis (Kr.) under the abdomen, or with 

 Gvqe Hippolyfes (Ki-.) in tlie branchial cavity. In a specimen infested with Clioi/iob-funia J. Sparre 

 Selmeider has observed a specimen of Hemiarthrnn, and on a specimen of Hipp. Garmardii, 

 under a large swelling on the right side of the animal, I have found eleven ovisacs and an 

 adult female of Chon. Hansen ii . as well as an adult male and a tiny female (smallei- than 

 the male) of Gyiir Hippolyfes, and besides, under the apparently normal left side of the 

 caiapace, a male of Gyge. In the species of the genus Erytlirops (order Mysidacea), G. 0. Sars 

 has found the Epicarid Aspidophryxvs peUalns G. O. S., and Giard and Bonnier have reserved 

 this name tor the form found on Er. erytinophtlialnms (Goes) [E. Goesii G. 0. S.), and 

 established a new species, A. Sarsii G. and B., for the form which lives on E. nricrophlhalniiis 

 G. O. S. Giard and Bonnier have found their type specimens of the latter species (the value 

 of which future examination will ha\e to decide) on the same specimen as their type 

 specimens of Aspidoecia Nornumi, and I have found a specimen of Aspidophryoivs on an 

 Er. eryfhrophfJtalnnis sent to me by Prof. Sars as infested with Aspidoecia, but this parasite 

 must have fallen off before tlie animals were sent to me, if it was ever there at all. 



The genus Sylon Kr., belonging to Rhizocephala, lives, as we know, on the ventral 

 side of the abdomen in some .species oi Hippolyte, but I have not found it on any specimen 

 infested with Choniosfoma. The remaining species belonging to Rhizocephala and Copepoda, 

 which are parasitic on Malacostraca, have all been taken on forms on which no Choniostomatidse 

 have been found. 



Together with Sphrnonelln parado.ra I have found repeatedly in the marsupium of 

 Bathyporeia several specimens of a species behjnging to the family Tyroglyphida' (the 

 order Acarida). 



Of other parasites I have only detected some Protozoa on the brancMse and the 

 marsupial plates in the material of Malacostraca with Choniostomatidae examined by me. 



So I have arrived at the result that there exists no connection at all between 

 Choniostomatidae and any of the other parasites of different orders found on the same 

 species of hosts. 



g. Nourishment. 



I cut a bit of skin of an Erythrops in the place where an A.sj)idoecia had been 

 attached, cleaned it with caustic potash from muscles and viscous substance, and discovered 

 a small hole, where the mouth of the parasite had its place. And this seems veiy natural 

 indeed; in the first place, the mandibles appear quite well qualified for producing such a 

 hole; secondly, the mouth is doubtless suctorial, and lastly, the female, which is permanently 



