THE SESSILE BARNACLES. 189 



The bocl^v was not preserved. It occurred with B. crenakus, one 

 of which grew upon the specimen figured. Though the opercular 

 valves resemble those of calcaratus from Shelikof Strait, the walls 

 are very different. It appears that this west American race has 

 the same wide variation in external form long known in Atlantic 

 balanoides. 



BALANUS CARIOSUS (Pallas). 



Plate 46 ; plate 47, figs. 1-lc. 



1788. Lcpas cariosa PALLAS, Nova Acta Academire Scientinrium Imperialis 

 Petropolitanse, vol. 2, p. 234, pi. 6, figs. 24A, 24 c. 



1854. Balanus cariosus Pallas, DAEWIN, Monograph, p. 273, pi. 7, figs. 

 3ff-3c. 



1S97. Bahnuis cariosus Pallas, WELTNER, Verzeichnis, p. 270. 



1903. Balanus cariosus Pallas, GRUVEL, Nouvelles Archives du Museum, 

 ser. 4, vol. 5, p. 140, pi. 4, fig. 13. " Golfe cle Georgie, Aingrique 

 (Agassiz), et de Cochinchine." 



1911. Balanus cariosus Pallas, KRUGER, Beitrage zur Cirripedienfauua 

 Ostasiens, Abhandl. der Math.-phys. Klasse der K. Bayer. Aka- 

 demie der Wissenschaften, Suppl.-Bd. 2, p. 54, figs. 108-111, pi. 1, 

 fig. 8; pi. 4, fig. 37 (Iterup, Kuril Is., Doctor Haberer, aud Todo- 

 hokke, Hokkaido, Doctor Doflein). 



Type-locality. The Kuril Islands. 



Distribution. -Bering Sea south to Oregon and to northern Japan; 

 in the littoral zone. 



Darwin's diagnosis : 



Parietes thick, formed by several rows of unequal-sized pores. Terguin nar- 

 row, with the \ipes beaked and the spur sharply pointed. 



The form is usually steeply conic, with a small orifice, but some- 

 times cylindric with the orifice large; dirty white. Sculpture of 

 many narrow, deeply cut, irregular ribs, usually provided with occa- 

 sional projecting points " from the manner in which these overlap 

 each other the shell almost appears as if thatched with straw." The 

 upper part in old individuals is generally eroded, irregularly rugose, 

 and pitted. Radii usually very narrow, often scarcely distinguish- 

 able as such; but in some cylindrical examples, such as plate 46, 

 figures 2, 2#, they become very wide, with strongly oblique summits. 

 The wall is ordinarily very thick, permeated with many unequal 

 rounded and angular tubes (pi. 40, figs. 1, 8). They have trans- 

 verse septa and become filled up and then eroded away in the upper 

 part of the cone. Sometimes the pores are almost filled up, in large 

 part obliterated, at the base. Within the basal edge the inside is 

 peculiarly roughened or has irregularly branching wrinkles. The 

 sheath is long, often over half the height of the cone, the space be- 

 tween it and the wall usually filled up solidly, and the opercular 

 valves lodge far within the orifice. 



