266 BULLETIN 93, UNITED STATES NATIONAL MUSEUM. 



This species is related to C. testudinaria, from which it differs by 

 having the sides of the well developed radii not dentate, the parietes 

 having salient longitudinal ribs which subdivide toward the base, 

 and the basal septa are fewer. 



I do not know that typical specimens of this species exist in any 

 American museum, but there are certain barnacles in the series be- 

 fore me which, while possibly referable to C. testud-inaria as varieties, 

 have some characters of the West African species, and may be 

 noticed here. 



I am giving names to these forms in order to call attention to 

 their characters which might otherwise be overlooked by those having 

 opportunity of seeing large numbers of turtle barnacles. Their 

 status as races can not yet be considered established. 



C. in. lobatibasis, new variety. A specimen from Osprey, Florida 

 (pi. 62, figs. 7, 7) , on Caretta, caretta, No. 2107, Academy Natural 

 Sciences, Philadelphia, has a large orifice and steep walls, which 

 are irregularly plicate or ribbed in the lower half, producing an 

 irregularly lobed periphery. The radii are rather wide, without 

 " teeth." The basal septa are less numerous than in C. testudinccria, 

 and there are rather small, deep cavities between them. Base of 

 sheath as in C. teslndnnn-nt, with many breaches, leaving only wide 

 and narrow pillars. Diameter 23 mm., height 9^ mm. 



C. m. creriatibasis, new variety. A group of three old specimens 

 (pi. 02, figs. 5, 5, Cat. No. 48196, U.S.N.M.), from the Isaac Lea 

 collection, locality and station unrecorded, have the orifice very large, 

 the radii partly simple, but a few show very weak traces of teeth. 

 Very close to the base there are numerous inconspicuous folds, and 

 the interstices between these, or part of them, form minute loops, 

 projecting into the septate base. (Seen on the right side in fig. 5.) 

 This rather inconspicuous character is not present in any of the 

 large series of ordinary testudinaria, which has passed under my eye. 

 The parietal cavities are particularly large and evenly developed. 

 The parietal septa are distinctly of four lengths those extending 

 to the inner wall, those extending half across the cavities, others 

 extending to the inner border of the outer wall, and the shortest 

 series at the peripheral margin. Specimens measure, diameter 43 

 mm., height 18 mm. ; diameter 37 mm., height 13 mm. 



The battered summits of the compartments testify to a life of hard 

 knocks, such as falls to the lot of most turtle barnacles. Moreover, 

 some thin laminae adhering to the base are probably from the logger- 

 head turtle. 



