SIPIIONCECETES. 
463 
AMP II IPOD A. 
NAT ATOM A. 
PODOCERIDES. 
Genus— SIPHONCECETES. 
Siplioncecelus. Kroyer, Nat. Tidsk. i. p. 491. Yoyage en Scand. pi. xx. 
fig. 1. Spence Bate, Cat. Amph. Brit. Mus. p. 268. 
Ann. Nat. Hist. 2 ser. xix. p. 149. Rep. Brit. Assoc. 
1855, p. 59. White, Pop. Hist. Brit. Crust, p. 196. 
Generic character. Superior antennee with a multi-articulate 
flagellum, and no secondary appendage. Inferior antennae 
having the flagellum not multi-articulate. Gnathopoda subequal, 
subchelate. Pereiopoda short and robust. Posterior pair of 
pleopoda very short, terminating in a single ramus tipped with 
hooks. Telson furnished with several rows of short, sharp 
teeth or spines. 
The body of the animals in this genus is not laterally 
compressed, and the coxae are very small. The eyes are 
situated on projecting lateral lobes of the cephalon. 
The superior antennae are shorter than the inferior, and 
are furnished with a multi- articulate flagellum, but do 
not carry a secondary appendage. The inferior antennae 
are developed nearly in the form of true legs, and 
generally consist, we believe, of seven joints; at all 
events the flagellum is never multi-articulate. The first 
two pairs of legs are subchelate, and nearly alike in size, 
the second being rather the larger. All the walking legs 
are short and tolerably strong. The posterior pair of 
caudal appendages terminate in a double-hooked branch. 
The middle tail-piece consists of a single lobe, furnished 
with numerous small teeth or spines. 
Kroyer, in his figure of the type of the genus, re- 
presents the posterior pair of caudal appendages as 
being double-branched, but if our observation be cor- 
