M. T. Thorell on the Species of the Argulidse. 443 



3. G. Kollari, Hell. 



Syn. Gyropeltis Kollari, Heller, Sitzungsberichte d. Kais. Akad. d. Wis- 

 sensch., Math.-Naturvvissenscli. CL, (1857) xxv. p. 102, taf. 1. 

 figg. 20, 21 ; taf. 2. figg. 1-3. 



Scutum cephalicum inverse subcordatum, amplum, omnes pedes 

 et basin caudse tegens; cauda brevis, ^-^ reliqui corporis 

 longitudinis jEquans^ inverse rotundato-ovata, postice parum 

 profunde incisa, laciniis brevibus obtusis ; pectinis dentes 3 

 breves, obtusi. — Longit. 12, latit. 9 millim. ( ? ). 



Hub. in America meridionali (Brasilia). Hospitium ignotum. 



?4. G. Lacordairei (Aud.). 



Syn. Dohps Lacordairei, Audouin, Annales de la Soc. Entomol. de France, 

 ser. 1. 1. vi. (1837), Bull. p. 13. 



Long, plus 15 millim. 

 }Iab. in America meridionali (Cayenne), in pisce Aymara dicto parasitans. 



Concerning this animal we have the following remarks from 

 the above-cited source : — 



" M. Audouin presente deux individus d^m crustace singulier, 

 qui a beaucoup d'analogie avec PArgule foiiace de Jurine, mais 

 qui en differe surtout par Fabsence de ventouses aux pattes an- 

 terieures, et par sa taille, qui depasse un centimetre et demi. 



'' Ce crustace a ete trouve k Cayenne par M. Lacordaire ; il 

 est parasite sur un poisson nomme Aymara, dont la chair est 

 tres-estimee, et qui vit dans toutes les rivieres. M. Audouiu 

 en donne la description et le regarde comme le type d'un nou- 

 veau genre, auquel il assigne le nom de Dolops. II dedie cette 

 espece k M. Lacordaire : 



" Dolops Lacordairei. Ce nouveau genre sara decrit en detail 

 et figure.^' 



That this Dolops Lacordairei is a Gyropeltis, or at least stands 

 very near this genus, may be regarded as certain. But although 

 the name Dolvps is older than Gyropeltis, it seems to me in every 

 respect more desirable to retain the latter appellation, inasmuch 

 as Audouin did not determine or clearly point out the characters 

 on which he founds the genus Dolops. No description of the 

 species has, as far as I can discover, been published. 



As at the most sixteen species of the family Argulidse are as 

 yet known, and as this number will undoubtedly be considerably 

 increased, it would be premature now to attempt to draw, from 

 what is known of the localities of these species, any general 

 conclusions as to the geographical range of the family. We may, 

 however, suppose with Kroyer that the great American continent 



Ann. ^ Mag. N, Hist, Ser. 3. Vol. xviii. 31 



