~ Ald A HISTORY OF RECENT CRUSTACEA 
Risso’s obscure descriptions entitle him to honour or grati- 
tude. In the present instance, it is said, he mistook the 
tail of the parasite for its head, and considered the appen- 
dages of the pleon to be ramified plumose antenne. 
Kvidently Latreille was puzzled by the description, for in 
1825, under the genus ‘Ichthyophile (Cymothoa, Leach), 
he says, ‘ L’ergina cervicornis de M. Risso me _parait étre 
un ichthyophile, ayant accidentellement un corps étranger 
(algue?) aux antennes.’ In this species it is observed 
that ‘the colour of the ovary and consequently that of the 
largest part of the body is of a brilliant carmine red.’ 
Gigantione, Kossmann, 1881. ‘The female has an 
almost circular outline, all the segments having un- 
branched prolongations. The three-jointed first antennze 
have the basal joint expanded so as to cover the oral 
region, just leaving space for the protrusion of the points 
of the mandibles. The tiny feet have a short pointed 
nail. The marsupial plates are very large. ‘The first 
pleopods form acuminate sacks with sparingly ramified 
out-growths on the surface; the following pairs are small, 
entirely ramose. ‘The male has the pleon distinctly seg- 
mented, with six pairs of oval sack-like pleopods. 
Gigantione Moebii, Kossmann, 1881 (see Plate XVIII), 
in Liippellia impressa, de Haan. 
Ione, Uatreille, 1818. The female has the side-plates 
well developed on the head and perzeon, those of the first 
five segments of the pleon arborescent, coralloid, the ap- 
pendages of the sixth segment simple, cylindrical, recurved 
at the extremity. The male has the second antennz seven- 
jointed, and the pleon furnished with six pairs of long 
cylindrical appendages. 
Ione thoracicus (Montagu, 1808), in Callianassa sub- 
terranea (Montagu), was first recorded from Devonshire. 
Ione cornutus, Spence Bate, 1864, in Callianassa longi- 
mana, Spence Bate. 
Tone vicina, Giard and Bonnier, 1890, in Callianassa 
truncata, Giard and Bonnier. 
Tone igebice, Giard and Bonnier, 1890, in Upogebia stellata 
(Montagu), 
