THE SESSILE BARNAOLES. 341 



PLATE 12. 



FIGS. 1-1&. Balanus tintinnabulum galapaganus Pilsbry. Hood Island, Gala- 

 pagos. Tergum and scuta of the type. Cat. No. 48003, U.S.N.M. 



Page 70. 



2, 2a, 2b. Balanus tintinnabulum azoricus Pilsbry. Terceira, Azores. Scuta 

 and tergum of the type. Cat No. 48004, U.S.N.M. Page 62. 



3-3d. Balanus algicola Pilsbry. Cape Town. Groups and solitary indi- 

 viduals growing on various algae. Cat. No. 15063, U.S.N.M. 



Page 72. 

 3e, 3f, 3ff. -Balanus algicola. Terguna and scuta of type, in group 3a. 



PLATE 13. 



FIGS. 1-le. Balanus tintinnabulum antillensis Pilsbry. St. Thomas, West 

 Indies. Type and paratype group, with opercular valves. Page 63. 

 2-2b. B. t. antillensis from bottom of a Cape Cod whaler, from the West 

 Indies. Lateral and basal views. Cat. No. 48005, U.S.N.M. In 

 fig. 2b a small specimen of Tetraclita radiata is seen attached. 

 2c, 2d, 2e. Tergum and scuta of the same. 

 Figs, le, 2-2&, natural size. 



PLATE 14. 

 Balanus tintinnabulum californicus Pilsbry. 



FIG. 1. Type and paratypes, San Diego, California. Cat. No. 9434a, U.S.N.M. 

 Natural size. Page 65. 



lar-ld. Opercular valves of type. 



2. Group on an oyster, San Diego. Cat. No. 9435, U.S.N.M. Natural 



size. 



3. Group showing the form with lengthened basis, near Santa Bar- 



bara, California. Cat. No. 43484, U.S.N.M. 



PLATE 15. 



FIGS. 1, la. Balanus tintinnabulum peninsularis Pilsbry. Groups. Cat. No. 



43487, U.S.N.M. Natural size. Page 66. 



2-2d. B. t. peninsularis. Cape St. Lucas. Type with its opercular valves, 



and a smaller specimen. 2b, 2c natural size. Cat. No. 43486, 



U.S.N.M. 



3. Balanus tintinnabulum concinnus Darwin. Inside of scutum. 



Page 69. 



4. Balanus tintinnabulum californicus Pilsbry. Basal edge of the 



wall of one of the type group. The spongy basis is seen near the 

 left side. Page 65. 



PLATE 16. 



FIGS. 1, 10. Balanus tintinnabulum coccopoma Darwin. Tergum and scutum 



of specimen from Panama. Page 68. 



2, 2a. Balanus tintinnabulum coccopoma Darwin. Group and outside of 



scutum. Bay of Panama. Fig. 2 natural size. 



3. Balanus tintinnabulum concinnus Darwin. Payta, Peru. Cat. No. 

 12417. Natural size. Page 69. 



4729 Bull. 9316 23 



