178 BULLETIN 91, UNITED STATES NATIONAL MUSEUM. 



Order POLYPLACOPHOEA. 



Family ISCHNOCHITONIDAE. 



Genus CALLOCHITON Gray. 



CALLOCH1TON CASTANEUS Wood. 



Cat. No. 186907, U.S.N.M., contains four valves of this species from 



Port Alfred (Coll. No. 277). Cat. No. 249828, U.S.N.M., contains 



two additional complete specimens from the same locality (Coll. 



No. 1100). 



Genus ISCHNOCHITON Gray. 



ISCHNOCHITON CRAWFORDI Sykes. 



Cat. No. 250603, U.S.N.M., contains a specimen from Port Alfred 

 (Coll. No. 1476). Cat. No. 187140, U.S.N.M., contains a single valve 

 from the same place (Coll. No. 686). 



ISCHNOCHITON CYANEOPUNCTATUS Krauss. 



Cat. No. 125380, U.S.N.M., contains a specimen obtained on the 

 United States Eclipse Expedition of 1890 at Cape Town. 



ISCHNOCHITON ONISCUS Krauss. 



Two lots of this species were obtained by William Stimpson on the 

 North Pacific Exploring Expedition: One, Cat. No. 122, U.S.N.M., a 

 complete specimen and a lot of valves, at the Cape of Good Hope; the 

 other, Cat. No. 143, U.S.N.M., one specimen at Simons Bay, Cape of 

 Good Hope. In addition to these there are 35 lots of this species, 

 which are extremely variable in color markings, in the collection of 

 the United States National Museum, from Port Alfred, as follows: 

 Cat. No. 187137, one specimen (Coll. No. 683); Cat. No. 187136, one 

 specimen (Coll. No. 682); Cat. No. 187138, one specimen (Coll. No. 

 684); Cat. No. 187140a, one valve (Coll. No. 686a); Cat. No. 249803, 

 three specimens (Coll. No. 1075); Cat. No. 249804, three specimens 

 (Coll. No. 1076); Cat. No. 249805, three specimens (Coll. No. 1077); 

 Cat. No. 249806, three specimens (Coll. No. 1078) ; Cat. No. 249807, 

 two specimens (Coll. No. 1079); Cat. No. 249808, three specimens 

 (Coll. No. 1080); Cat No. 249809, three specimens (Coll. No. 1081); 

 Cat. No. 249810, three specimens (Coll. No. 1082); Cat. No. 249811, 

 three specimens (Coll. No. 1083); Cat. No. 249812, one specimen 

 (Coll. No. 1084); Cat. No. 249813, three specimens (Coll. No. 1085); 

 Cat. No. 249814, two specimens (Coll. No. 1086); Cat. No. 249815, 

 three specimens (Coll. No. 1087); Cat. No. 249816, two specimens 

 (Coll. No. 1088); Cat. No. 249817, three specimens (Coll. No. 1089); 

 Cat. No. 249822, two specimens (Coll. No. 1094); Cat. No. 250606, 

 one specimen (Coll. No. 1479); Cat. No. 250608, one specimen (Coll. 

 No. 1481); Cat. No. 250609, one specimen (Coll. No. 1482); Cat. No. 

 250610, two specimens (Coll. No. 1483); Cat. No. 250611, two speci- 



