THE SESSILE BARNACLES. 357 



Plate 72. 



Figs. 1, lo. Chthamalus challengeri tloek. Scutum and tergum. Matsushima. 



Page 307. 

 2, 2a. Scutum aud tergum. Ayukawa. 



3. Group growing on TetracUta. Yokohama. 



4, 4a. Scutum and tergum. Japan, on Balanus cariosus. 



5, 5a. Chthamalus malayensis. Malay Peninsula. Scutum and tergum. 



Page 310. 



G,6a,Qb. Chthamalus moro. Zamboanga, Mindanao. Group on TetracUta 



scabrosa. Scutum and terginn. Page31L 



Plate 73. 



Figs. 1, 16. Chthamalus caudatus Pll.sbry. Scutum, tergum, and top view of 



the wall on the tergum of JUitella. Catbalonga, Samar. Cat. No. 



4S087, LT.S.N.jr. Page 314. 



2. Chthamalus irithersiFiMiry. Top view. Page 312. 



2a~2d. Opercular valves of the type-specimen. 



2e. Rostrolateral compartment, inside view. 



3-3b. CJithamalus dalli Pilsbry. Top view, scutum and tergum. Una- 



laska. Cat. No. 48069, U.S.N.M. Page 316. 



4,4a. Chthamalus scabrosus Darwin. Scutum and tergum of a specimen 



from Valparaiso. Cat. No. 48089, U.S.N.M. Page 323. 



Plate 74. 



Figs. 1, lb. Chthamalus fissus Darwin. Scutum, tergum, and group on the 

 shell of Mytilus californianus, San Diego, California. Page 317. 

 2,2a. Chthamalus anisopoma Pilsbry. Left tergum and scutum of the 

 type. Gulf of California. Page 317. 



2b, 2c. Right scutum and tergum of the same individual, drawn to the 

 same scale as figs. 2, 2a. 

 2d. Exterior of scutum of an unusually well-preserved individual. 

 2e. Carina, interior view. 

 2/. Part of the group, enlarged. 



Plate 75. 



Fig. 1. Chthamalus iiiiperalrix Pilsbry. Interior of rostrolateral com- 

 partment. Page 320. 

 la. Interior of lateral compartment. 



lb. Group, seated on a stone ; a nearly unworn individual in the loAver 

 median part. 

 Ic, Id. Scutum and tergum, interior, 

 le. Carina, interior view. 

 2. Chthamalus panamensis I'ilahry. Exterior of scutum. Page 319. 

 2a, 2b. Two individuals of the typical lot. 



2c. Exterior of tergum. 

 2d, 2e. Interior of scutum and tergum of the type. 



Plate 76. 



Clithamalus hembeli Conrad. Page 324. 



Figs. 1, la. Napili Harbor, Maui. Cirri and penis. 



2, 2a. Hilo, Hawaii. Tergum and scutum of right-hand specimen, fig. 2b. 

 2b. Pair of old specimens. 

 2c. Scutum and tergum united, inside view ; same specimen. 



4729°— Bull. 93—16 24 



