180 PROCEEDINGii OF THE NATIONAL MUSEUM. vol.37. 



Shell ovate oblong, with eight overlapping valves within a narrow 

 border covered with flat pavement-like scales; whitish or olive, very 

 closely and regularly striped with brown or lavender-colored con- 

 centric lines, which converge forward on the middle of the valves. 

 Interior pale blue. Length about 50 mm., when full grown. 



This is one of the most elegant and characteristic of the numerous 

 chitons for which this province is noted. 



CHITON GRANOSUS Frembly. 



Chiton granosus Frembly, Zool. Journ., vol. 3, 1829, p. 200, suppl. pi. 17, fig. 

 1. — Reeve, Conch. Icon., 1848, Chiton, pi. 5, fig. 27. 

 Barquillo. Collected at MoUendo. 



Distribution. — From Magellan Straits north to Tumbes, Peru. 



Shell black, having a white stripe on each side of the central line, 

 between the stripes clouded with whitish; surface sculptured with 

 radiating lines of bead-like pustules; inside whitish, more or less 

 clouded with olive gray. Length about .40 mm. 



This species like the other chitons is of no economic importance. 



CH.ffiTOPLEURA HENNAHI Gray. 



Chiton hennahi Gray, Spicilegia Zool., 1828, p. 6, fig. 11. — Sowerby, Conch. 

 111., 1841, Chiton, figs. 1, 33. 

 Barquillo. Callao, 5 to 7 fathoms, and from rocks at the north end of Callao water 

 front. 



Distribution. — Callao, Peru. 



Shell brownish, smooth, sometimes marked with red or greenish 

 white; girdle or border leathery, with short hairs easily rubbed off; 

 inside white, brown under the beaks of the valves. Length about 40 mm. 



ACANTHOPLEURA {COREPHIUM) ECHINATA Barnes. 



Plate 23, fig. 6. 

 Chiton echviatus Barnes, Am. Journ. Sci., vol. 7, 1823, p. 71, pi. 3, figs. 4, 4a. 

 Chiton spini/erus Frembly, Zool. Journ., vol. 3, 1827. — Sowerby, Conch. 111., 1833, 

 Chiton, fig. 47. 

 Barquillo. From rocks along shore on the northeast side of San Lorenzo Island, 

 Callao Bay. 



Distribution. — From Valparaiso, Chile, northward to Paita, Peru, 

 and the Galapagos Islands. 



Shell elongate, solid, carinated along the dorsal ridge, the sides of 

 the central areas engraved with fine flexuous grooves; color dark 

 brown; lateral areas with several radiating lines of pustules; girdle 

 broad, leathery, with strong projecting spines. Length 100 mm. or 

 less, according to age. 



This and the following species are particularly characteristic of this 

 zoological province. 



The name "barquillo," used for these animals by the fishermen, is 

 probably derived from the resemblance, when the animal is placed 

 on its back, to a little boat. 



