832 M. A. Boeck on the Amphijjoda 



can satisfy us as constant 'and exclusive characters. A 

 better limitation was obtained by this family when Spence 

 Bate transferred the genus Amphitoe, as reduced by Dana, to 

 the Corophida? ; but to characterize this family, with him, as 

 a tribe (Natatoria) , and to place the Corophida? under a tribe 

 (Domicola), cannot be regarded as satisfactory; for several of 

 the latter do not inhabit tubes formed by themselves, whilst 

 some Gammarida? do so, such as the genus Haphops esta- 

 blished by Professor Lilljeborg. The best character seems to 

 me to be that set up by Bruzelius, that the abdominal appen- 

 dages in the Corophida? are very thick, often beset with spines, 

 and that the branches of the last pair of leaping-feet are most 

 frequently cylindrical. To this may be added, that the inner 

 lamella of the first pair of maxilla? is small, thick, or obsolete, 

 and only furnished with simple, not quadrifid hairs, whilst 

 in the Gammarida? the abdominal appendages and the branches 

 of the last pair of abdominal feet, as well as the inner plate of 

 the first pair of maxilla?, are lamellar. 



Anonyx, Kr. — To this genus, already including a great 

 number of species (which are just as difficult to distinguish 

 from one another as the genus is easy to recognize at the first 

 glance), I can add four new species from our west coast. Be- 

 sides the usual characters cited for this genus, it may be stated 

 that the inner lamella of the first pair of maxilla? is, as in the 

 Orchestida?, very long and narrow, and furnished with two 

 strong and long seta?, closely ciliated on the margins. To 

 this, however, A. tumtdus, Kr., and A. Kroyeri, Bruz., are 

 exceptions ; and these also differ in many other respects 

 from the rest of the species, and constitute transitions towards 

 the following genera. The respiratory lamella? are broad, and 

 the ovigerous lamella? long and narrow, beset with single, scat- 

 tered, but long seta?. 



The new species discovered by me are : — 



1. A. serratus, mihi. — This species and the following one 

 belong to those in which the lower posterior angle of the third 

 abdominal segment does not form a hook. Its eyes are large 

 and become nan-owed upwards. The first joint of the peduncle 

 of the superior antenna? is long, thick, and cylindrical, the 

 other two very small ; the flagellum is formed of seven joints, 

 of which the first is as long as the following three together ; 

 the secondary flagellum is four-jointed. The third and fourth 

 joints of the inferior antenna? are of equal length. The fla- 

 gellum is formed, in the female, of eleven joints, in the male 

 of about twenty. The parts of the mouth are much produced 

 and narrow ; the mandibles acuminated at the apex, and from 

 that point to the long narrow masticatory tubercle extends a 



