258 CHITONID^. 



Limapontia zonata. 



Niohe zonata, Girard, Proc. Bost. Soc. Nat. Hist. iv. 211 (1852), 

 Limapontia zonata, Stimpson, Check Lists, 4 (1860), no description. 



Less than a line in length, its body and head not quite so much 

 separated as in L. liniacina. It has a pale reddish hue, with trans- 

 verse bands of white, which have suggested the specific name of 

 zonata. Boston Harbor (GiVari/). 



Sub-Class PROSOBRANCHIATA * 



Gills pectinate or plumose, placed in a mantle-cavity above the 

 neck, or under the mantle on the left side. Heart situated behind 

 the gills. Sexes distinct. Abdomen well developed, usually spiral 

 and protected by a shell. Adult and larva shell-bearing ; larva fur- 

 nished with deciduous ciliated fins springing from the sides of the 

 head. 



Family CHITONID^, Guilding. 



Shell not spiral, shield-shaped, composed of numerous pieces ; 

 aperture very large. 



Genus CHITON, Lin. 1758. 



Shell oval, consisting of eight arched pieces, arranged across the 

 body of the animal in a series overlapping each other, their ends 

 set in the skin which forms a rim around them. 



Chiton apiculatus. 



Fig. 20. 



Dorsal triangles with series of elevated points ; lateral triangles with scattered, 

 elevated dots. 



Chiton apiculatus. Say, Amer. Conch. No. 7 ; Binnet's ed. 231. — Sowekby, Conch. III. 

 140. -De Kay, N. Y. Moll. 164, pi. 10, figs. 201, 202. — Stimpson, Check Lists, 4 

 (1860). 



* This portion of the work was not completely arrnnpocl for the press by Dr. Gould. I 

 have worked it up from his interleaved copy of the first edition, containing his rough notes 

 of corrections, additions, references, &c. 



The classification is that adopted by Dr. Gould. — W. G. B. 



