Classification of the Thalassinidea. 541 
Genus Jaxza, Nardo, 1847. 
[= Calhazxis, Heller, 1856. } 
Definition : “ Laomediide which have on the maxillipeds 
of the first pair a lash to the exopodite and a podobranch, 
the chelze in the legs of the first pair slender, and those of 
the second pair subchelate.” 
Species : 
Type. J. nocturna, Nardo, 1847. Sinonimia moderna* [=C. adriaticay 
Heller, 1856]. 
Family Thalassinide, Dana, 1852. 
Definition: ‘ Thalassinidea with a rostrum of fair size; a 
linea thalassinica ; antennular flagella of moderate length, no 
vestige of antennal scale + or fixed thorn; the first and second 
pairs of legs subchelate {, the rest simple; mastigobranchs 
on legs 1-4, podobranchs on legs 1-3, no pleurobranchs, 
the gills partly trichobranch, partly with broad plates; the 
pleura of the abdominal segments small; the third to fifth 
abdominal limbs without appendix interna, the branches of 
the abdominal limbs narrow, and the last pair without suture 
on endopodite or exopodite.” 
Genus: Thalassina, Latr., 1806. 
Species § : 
Type. 7. anomala (Hbst.), 1801. Naturges. Krabben u. Krebse, iii. ii. 
[=T. scorptonordes, Latr., 1806,=7. maxima, Hess, 1865, ?= 7. 
gracilis, Dana, 1852.| I. 
T. chilensis, Steenstrup & Liitken, 1861. Nat. Foren. Vidensk. Med- 
delelser. G. 
Family Callianasside, Bate, 1888. 
Definition: “ Thalassinidea whose rostrum may be either 
of a good size or small; which have the linea thalassinica, the 
antennular flagella short or of moderate length, the antennal 
scale quite vestigial, and no antennal thorn; the legs of the 
first pair usually chelate or subchelate, but sometimes simple, 
those of the second pair chelate or simple, those of the third 
and fourth pairs simple, and those of the fifth pair simple, 
subchelate or chelate; the legs without podobranchs and 
* See also Ann. Ist. Venet. xiv. 
+ There are some small irregular Imobs between the second and third 
joints of the antennal stalk, but Boas shows that neither of these repre- 
sents the scale. 
{ Bate’s figure is quite wrong in regard to the second leg. 
§ According to Ortmann (Bronun’s ‘ Thierreich,’ vy.) there is probably 
only one species. 
