276 Dr. F. Miiller on a new Genus of Amphipod Crustacea. 



distinction ; and the new species cannot be the Astrcea (Heli- 

 astraa) Prevostana, Ed. & Haime*, which only differs from A. 

 Raulini by its closer calices, thicker walls, and less developed 

 costae. The columella is well developed in this last species, if it 

 be like A. Raulini. MM. Milne-Ed wards and J. Haime do not 

 figure or positively describe their " unique echantillon " " en 

 assez mauvais etat." 



Locality, Bed No. 1 (Adams), Malta. Coll. Geol. Soc. 



EXPLANATION OF PLATE XI. 



Fig. 1. «, corallite of Canocyathus Adamsi; b, its calice, magnified 

 2 diameters. 



Fig. 2. a, corallum of Heliastrcca Forbesi, natural size ; h, usual appearance 

 of badly preserved specimens ; c, calices, natural size ; d, calices, 

 magnified 4 diameters ; e, monstrous calice with seven systems, 

 magnified 4 diameters ; f, calice without a columella, magnified 

 4 diameters. 



XXXI. — Description of a new Genus of Amphipod Crustacea. 

 By Dr. Fritz Muller. 



[Plate X.] 



Batea, nov. gen. 



Antennae simple. Coxae of the first pair of gnathopoda rudi- 

 mentary, those of the second pair of gnathopoda and the first 

 two pairs of pereiopoda largely developed. Coxa? of the second 

 pair of pereiopoda deeply excavated upon the upper part of the 

 posterior margin. First pair of gnathopoda rudimentary, con- 

 sisting of coxa and basis only ; second pair of gnathopoda sub- 

 chelate. Mandibles having an articulated appendage. Maxilli- 

 peds having a squamiform plate on both the basis and ischium 

 joints. Fourth and fifth pairs of pleopoda with styliform rami, 

 sixth pair with subfoliaceous rami. Telson single, deeply cleft. 



Species Batea catharinensis, F. M. 



I will here add some remarks on the sexual differences of this 

 interesting species. The pereion is somewhat longer and higher 

 in the female ; the antennas of the same are shorter. The first 

 joint of the peduncle of the upper antennas has three, the second 

 four, fasciculi of hairs on the inferior side in the male ; they are 

 wanting in the female. The long setae at the extremity of the al- 

 ternate articles of the flagellum of the first antennae are directed 

 downwards in the female, backwards in the male. The third and 

 fourth joints of the peduncle of the lower antennae have fasciculi 



* Op. cit. vol. ii. p. 475. 



