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BULLETIN 93, UNITED STATES NATIONAL MUSEUM. 



Specimens from Bermuda which I have seen agree with Darwin's 

 description. The irregular, strongly marked ridges of growth on 

 the lower part of the rostrum show that individuals 8 to 9 mm. long 

 are old. The maximum length of rostrum given by Darwin is .3 

 of an inch, or about 7.5 mm. 



Professor Verrill's var. cuspidatus, from Bermuda, is described as 

 follows : 



Our specimens differ as a variety from the typical form described by Darwin, 

 in having the summit of the rostrum divided into four or six acute denticles ; 



FIG. 74. BALANUS DECLIVIS. a, CIRRUS iv, THE SPINES OMITTED. Z>, LOWER PART OF THE 



SAME. C, FIFTH SEGMENT, AND d, TENTH SEGMENT OF CIRRUS IV. e, 22D SEGMENT OF 

 CIRRUS VI. 



it is very convex and considerably incurved. The summit of the carina is 

 bilobed by a narrow incision. The base is membranous and very obliquely 

 placed, owing to the downward prolongation of the rostrum, as in the type. 

 Long Bird Island, on the flats, embedded in a blackish massive keratose sponge 

 (Spongia, sp.), which often lives half buried in the calcareous sand at low tide, 

 and which also harbors a small Alplieus and several isopod crustaceans. 



The denticles at the summit can only be produced by breakage or 

 erosion, and their presence in Professor Verrill's specimens is prob- 

 ably accidental an individual and not a racial character. Some 

 specimens I have seen show faint gray and white longitudinal stripes 

 near the summit of the rostrum, possibly indicating differences in the 



