116 AMERICAN MARINE CONCHOLOGY. 
Genus TERGIPES, Cuvier. 
Ann, du Mus., xix. 1812. 
1. T. pEspecra, Johnston. Fig. 240. 
(Eolis.) Mag. Nat. Hist., viii. 378, f. 35¢. 
Animal colorless, with a zigzag olive stripe along the back; 
branchiz large, ovate, in a single series along each side; dorsal 
tentacles long; angles of foot not produced. 
Length 6, breadth 1.25 mill. - 
Massachusetts; Scotland. 
2. T. ayMnoTa, Couthouy. Fig. 241. 
(Holis.) Bost. Journ. Nat. Hist., ii. 69, t. 1, f. 8. 1838. 
Animal small, tapering to a fine point, watery white; tentacles 
short, the posterior pair minutely serrated; branchiz in seven 
lateral clusters of about five each, slightly club-shaped, having a 
reddish-brown centre. 
Length 25, diam. 2.5 mill. 
Massachusetts. 
Genus CALLIOPZA, Orb. 
Mag. Zool., t. 108. 1837. 
1. C. FuscaTA, Gould. Fig. 241a. 
Invert. Mass., edit. ii. 250, t. 16, f. 218-221. 1870. 
Animal semicylindrical, attenuated behind, dark slate-colored ; 
head not distinct, excavated in front ; tentacles two, long, pointed; 
branchiz long, club-shaped, slender at base, alternating in two 
parallel rows on the two posterior thirds of each side, the lower 
series much the smaller; foot bilobed in front, contracted poste- 
riorly. 
Length 7.5, diam. .8 mill. 
Massachusetts. 
Family HERM AIDA. 
Synopsis of Genera. 
Tentacles two, longitudinally folded ; head without lobes; gills elongate, 
papillose, smooth, arranged along the sides of the back.. 
HerRM#A, Lovén. 
Head without tentacles, produced into a lobe on each side; gills papillose, 
_ arranged in transverse rows on the sides of the back. 
ALDERIA, Allman. 
Tentacles two, simple, undefended, contractile, sublateral; a large labial 
veil, produced on each side into an oblong, flat lobe ; gills simple, papil- 
lose, lateral, in a simple series on each side of the back ; foot rather 
broad. Cuiaura, Lovyén. 
