500 DESCRIPTION OF THE MUSEUM. 



cases opposite to the parrots. This order is also 

 divided into four families ; that of the dors ales 

 comprehends two genera, the arenicola and the 

 siliquaria. The arenicola lives in the sand and 

 makes no tube. There is but one species known, 

 which has been named piscatoria, because fisher- 

 men use it as a bait. It is found in abundance 

 on our shores. The siliquariae form a calcareous 

 lube ; we have seven species of them. 



The family of the maldanew comprehends the 

 genera dentalium and clymene; we have eleven 

 species of the first and none of the second. The 

 family amphitrite consists of four genera, the 

 pectinaria and the sabellaria, which form their 

 tubes of grains of sand stuck together by a gluti- 

 nous substance ; the terebella, whose tube is com- 

 posed of small shells, and the amphitrite with 

 a membranous tube ; we have two species of 

 this genus. The last family, that of the serpulece, 

 comprehends, 1 st, the genus spirorbis, extremely 

 small animals which attach their tube to shells 

 and other marine substances: we have five spe- 

 cies of them. 2d. The serpula, of which there 

 are nineteen species in the cabinet, and among 

 them several very rare ones, brought from the 

 South seas by MM. Peron and Lesueur. 3d. The 

 vermiUa, of which we have seven species: one 

 of them, v. rostrata, enveloped in a madrepore, 



