412 APPENDIX. No. IV. 



kt. 2, 41, 0, E. long. 9, 16, 0, both having a spinous process on each side of 

 their shell, near its opening. One species is beautifully sulcated transversely, 

 and the other but sUghtly so. 



Hyalcea tridentata (vulgarly called the chariot Anoraia) was also taken in 

 abundance in the Gulph of Guinea. 



Gasteeopoda. 



Jantlmiajragilis was the only species of this class that was brought home ; 

 all the rest, as well as the collection of the species of the following class, 



ACEPHALA, 



were lost. 



ClEElPEDES. 



Nine new species of Barnacles were discovered, all of which are very inte- 

 resting; since they augment especially the genus Cineras, of which but two 

 species only were known, and also two divisions of Hill's genus Pentalasmis, 

 of which hkevvise very few have been described. 



Sp. 1. Cineras ChelonopMlus. Body lanceolate, peduncle abrupt, upper scales 

 small and acuminated behind, the hinder scale straight and linear. 



Obs. The pm-plish stiipes of this species are very faint, and the scales 



beneath the legs ai-e covered by a thin membrane, which renders them 



very opaque. The space between the superior and posterior scales is 



very great. A large quantity occurred adhering to the legs, neck, and 



shell of some turtles that were taken in 36, 15, N. lat. 16, 32,0 W. 



long. See page 'J. 



Sp. 2. Cineras Cranchii. Body obUquely truncated above; the peduncle rather 



abrupt, upper scales hnear with obtuse extremities, hinder scale with a 



subgibbose apex. 



Obs. The vittae are three on each side, very strong ; the two anterior 

 ones are often interrupted. 

 Sp. 3. Cineras Oljersn. Body above acuminated, upper scales with both extre- 

 mities (especially the hinder one) acuminated, hinder scale at its middle 

 subgenictdated. Found on Fucus natans (Linn.) 



