47() 



^Ir. L. A. Bonaiiaile on the 



II. Phyllobrancbiate. Tenartbrobranchs. Limbs 

 on second abdominal segment of male. 



1. Artbrobranehs stand on side of tborax. 



Second autenuas bave o-jointed stalk and 

 usuiilly a spiniform scale. [Abdomen not 

 folded" against tbe tborax. Tbird maxilli- 

 peds witbout mastigobrancb.] Chirostylidae. 



2. Artbrobrancbs normally placed. Second 



antennae bave 4-jointed stalk and no scale 

 (or vestiges only), 

 i. Abdomen not folded against thorax. Tbird 



maxillipeds with mastigobranchs Galatheidse. 



ii. Abdomen folded against thorax. Body 

 crab-like. Third maxillipeds without 

 mastigobranchs Porcellanidae. 



Key to the Subfamilies of the Galatheidee. 



I. Eyes well developed. Exopodites of third 



maxillipeds with 1-jointed " flagella " .... Galatheince. 



II. Eyes reduced. Exopodites of third maxilli- 

 peds without flagella ... Muiiidopsina. 



Key to the Families of the Thalassiuidea. 



I. No linea thalassiniea. Both movable and 

 fixed antennal thorns present, though some- 

 times minute (? absent in Scytoleptus). Ab- 

 dominal pleura large. [Last endopodite 

 without suture. Second legs chelate.] .... Axiidas. 

 II. Linea thalassiniea present (except Callia- 

 jiidea). Fixed antennal thorn wanting ; 

 scale reduced to a flattened vestige or wanting. 

 Abdominal pleura usually small. 



1. Sutures on endopodite and exopodite of 



sixth abdominal limbs. Abdominal pleura 



of a good size Laomediidae. 



2. No sutures on sixth abdominal limbs. Ab- 



dominal pleura small. 

 i. Second leg chelate or simple. No podo- 



brancbs on legs. Abdominal limbs 3-6 



broad. A vestige of antennal scale 



remains Callianassidae 



ii. Second leg subcbelate. Podobranchs on 



legs 1-3. Abdominal limbs all narrow. 



No vestige of antennal scale Thalassinidae. 



II, 



Key to the Subfamilies of the Callianassidae. 



Rostrum large. Legs of first pair equal. No 

 appendix interna on abdominal limbs 3-5 . . Upogebiince. 



Rostrum small. Legs of first pair unequal. 

 An ofipendix interna on abdominal limbs 3-0. Callianassinee. 



