CABIROPSID Z—CRYPTONISCID & 401 
Cabirops lerncesdisesides, Kossmann (1872), was found 
in the brood-cavity of a Bopyrus from the Philippines. To 
this genus Giard and Bonnier approximate Cryptothiria (?) 
marsupialis, Sars, reported to be parasitic on two species, 
Eurycope cornuta and Ilyarachna lon jicornis. The female 
only of this parasite is known. It is a simple pellucid 
broadly bilobed sack, narrowed in front, filled with eggs, 
with an ovate oral area, and no appendages. 
Podascon, Giard and Bonnier, 1889. ‘ All the body of 
the female is, so to speak, transformed into a vast incuba- 
tory chamber, enclosed by two lateral plates extending from 
the first to the fifth segment of the perzeon and united 
along the median line so as merely to leave at either end 
an opening for the passage of water.’ 7 
Podascon Dellavallei, Giard and Bonnier, 1889, on the 
Amphipod Amwpelisca diadema (Costa). When first de- 
scribed, this was the only known instance of an Isopod 
parasitic on an Amphipod. New forms have since been 
found by M. Chevreux on three other species of Ampelisca. 
Also a Cryptoniscus-form found by Gourret on Leucothoe 
spinicarpa in the Ascidian Phallusia gelatinosa, may in the 
opinion of MM. Giard and Bonnier prove to belong to 
the Cabiropside. A Cryptoniscus-form found by myself 
among the eggs of an Onisimus plautus (Kréyer) from the 
Arctic regions, closely agrees with the Hemuioniscus balant 
of Buchholz, which is a member of the next family. 
Family 5.—Cryptoniscide. 
They are parasitic on Cirripedes, chiefly on the para- 
sitic Rhizocephala. It is reasonable to believe that the 
Rhizocephala did not begin their existence as parasites, 
but descended from independent Cirripedes. Fritz Miiller 
ingeniously suggests that in becoming parasitic they took 
with them their own parasites, the Cryptoniscide. Giard 
and Bonnier further suggest that the Entoniscide and 
Bopyride were introduced to the higher Crustacea by an- 
eestors parasitic on Rhizocephala, and that in course of 
time they found their advantage in exchanging an indirect 
for a direct parasitism. 
