M A I I D E A. 1(J9 



Resembles closely the trispinosa, but differs widely in its propor- 

 tions, the breadth across the lateral spines being much greater in 

 proportion to the length. The surface is very strongly porcelainous 

 after removing the villous coat, and in the specimen thus examined, it' 

 had a whitish flesh colour. There is a very minute point on the sides 

 of the anterior part of the stomach region. The horns of the beak 

 are divergent, but rtot widely so. The anterior spinous process of the 

 basal joint of the outer antennas projects its whole length beyond the 

 margin of the carapax, between the beak and the eyes. The anterior 

 legs are much longer than the second pair, and the second and follow- 

 ing pairs are subequal, the second a little the longest. The female 

 abdomen is round-elliptical. 



GENUS TIAKINIA, Dana. 



Oculi non retractiles, orbitd tubiformi inclusi. Rostrum bifidum, cornu- 

 bus plerumque contiguis. Carapax subpyrifarmis, tuberculatus aut pus- 

 tulatus, tuberculo cardiaco tuberculis tribus aut pluribus facto. Arti- 

 culus antennarum externarum Imus latissimus, spind apicali non 

 armatus, angulo externo-apicali interdum paulo saliente et subacuto. 

 Spina prceoi-bitalis promineiis. Pedes \mi 2dis non longiores. 



Eyes not retractile, enclosed in a tubular orbit. Beak bifid, horns for 

 the most part contiguous. Carapax subpyriform, tubercular or 

 pustulous above, the cardiac tubercle or prominence consisting of 

 three small tubercles. Basal joint of outer antennas very broad, 

 not armed anteriorly with a spine, outer angle sometimes a little 

 salient and subacute. Praeorbital spine prominent. Anterior feet 

 not longer than second. 



The genus Tiarinia includes the Pericera cornigera and some other 

 species of Pericera. They differ from Pericera in the beak, the cha- 

 racter of the surface, the basal joint of the outer antennae, and also in 

 less tendency to a triangular form in the outline. Moreover the ante- 

 rior legs are not longer than the second pair; and the cavity for the 

 pair of inner antennae is not wider than long. When the first basal 

 joint of the outer antennae has a spine anteriorly, it is a prominence of 

 the outer angle, and not a process near the articulation with the next 

 joint. 



28 



