60 BULLETIN 93^ UNITED STATES NATIONAL MUSEUM. 



It sooms rathor likely that B. t. occator was the origmal Lepas 

 crispata of Schroter, but as he gave no description or figure of the 

 tergum, I do not see that his form can be identified with certainty. 



BALANUS TINTINNABULUM VOLCANO, new subspecies.. 



Plate 11, figs. 2 to 2e. 



? Balanus tintinnabulum, var. crispatus Schroter, Darwin, Monograph, pp. 195, 

 201, pi. 1, fig. h. Not Lepas crispata Schroter. 



Type.— Cat. No. 43488, U.S.N.M. Japan, collected by H. 

 Loomis. 



A large barnacle with the conic shape of typical B. tintinnahulum, 

 nearly smooth except for minute, irregularly scattered and downwardly 

 projecting acute points or very short spines on the parietes, most 

 numerous on the rostral and lateral compartments. Purplish lilac, 

 in places deep slate-violet, where worn becoming pale smoke-gray. 

 Radii wide, transversely striate, with level summits. Sheath v/hitish 

 or pale flesh tinted, Carinorostral diameter 58 mm.; height 47 mm. 



Scutum flatter than in B. t. tintinnabulum, with the basi-tergal 

 corner but little cut off, tlie deflected tergal segment very small; exterior 

 finely but strongly ribbed longitudinally, the ribs prominent on the 

 growth-ridges, which are deeply scalloped by thorn. The adductor 

 ridge is high and rather massive. 



The tergum is similar to that of typical tintinnabulum, white with, 

 a buff cuticle when unworn, having narrow growth ridges and rather 

 faint traces of fine longitudinal striie. Spur about twice its own 

 width from the basiscutal angle. 



Tliis subspecies is well characterized by the flat scutum, its tergal 

 segment much less deflected than in B. t. occator, its surface radially 

 costulate over the growth-ridges. The parietes are rathor sparsely 

 armed with minute spines; size large, colore dull. B. t. occator is 

 paler, white or violaceous, the size smaller, and the tergum quite 

 different. It is often profusely spinose, the spines larger than in 

 B. t. volcano. Probably the latter will be found sometimes without 

 spines. 



In two rather large and strong specimens in the collection of the 

 Academy of Natural Sciences, which I refer to B. t. volcano, the 

 parietes are somewhat rugose, and aU the compartments have minute 

 spines. The adductor ridge of the scutum is moderately developed 

 in one, low and rounded as in typical tintinnabulum in the other. 

 They grew on wood, probal)ly ships. 



B. t. volcano is probably equivalent to part of Darwin's B. tin- 

 tinnabulum var. crispatus Schroter. I do not believe that it can be 

 the Lepas crispata of Schroter. Tliis species, as defined by Schroter,* 



1 Lepas crispata Schroter, Einleitiing in die Conchylienkeiintniss nacli Linne, vol. 3, 1786, p. 534, pi. 9, 

 fig. 21. 



