1304 



CRUSTACEA. 



Length, one-sixteenth of an inch. Body within the shell, white. 

 The shell is marked with minute parallel ridges, seen only with a 

 high lens. 



The setse of the second pair of antennae were a little bluish, and 

 nearly half as long as the shell. In profile, the upper part of the 

 front margin, for about one-fourth of the height, projects a little beyond 

 the outline below. 



Anterior to the mouth there appeared to be a pair of simple eyes, 

 the two rather distant. 



Legion II. PHYLLOPODA. 



The larger subdivisions or tribes in this section are mentioned and 

 described on a preceding page. As no specimens were collected by us, 

 we mention merely the known genera and their characteristics. 



Tribus I. ARTEMIOIDEA. 

 Fam. I. ARTEMIADiE.* 



Cephalothorax multiannulatus usque ad caput, testa nusquam tectus. 

 Pedes numerosi, foliacei. 



* Branchipoda, Leach; BrancHpiens, Edw.; Branchipidae, Burmeister, on Trilobites; 

 Branchipusidse, Baird, Trans. Berw. Nat. Club, 1845; Branchipodidse, Baird, Brit. 

 Entomost., 38. As the generic name Branchipus is not retained, it cannot properly be 

 used for deriving the name of the family. The name Branchipus, moreover, is not more 

 applicable to the species than it is to those of Limnadia or Apus, and there is not there- 

 fore any special reason for using it. We therefore derive the names of the tribe and 

 family from another word. We take Artemia rather than Chirocephalus as the origin of 

 these names, partly because it is shorter, but primarily because the peculiar head appa- 

 ratus of Chirocephalus, to which the name alludes, is not a necessary distinction of the 

 tribe or family, although characterizing the subfamily so-called. In the rejection of this 

 generic name, we follow Dr. Baird (Brit. Entomost., 40), who shows that Schoeffer's 

 Branchipus was probably of another genus. 



