LITHOTRYA DORSALIS. 351 



Cirripedes, as shown by the calcareous basis, — by the 

 manner in which the scuta and terga are locked together, 

 — by the two little fans of muscle attached to near the 

 basal points of the terga, — and perhaps by some of the 

 characters of the tropin ; nevertheless, this affinity is far 

 from being well-marked, and I think is hardly so plain as 

 in Pollicipes mi tell a. 



I. LlTHOTRYA DORSALIS. PL VIII, fig. 1 CI ' . 



Lithotrya dorsalis. G.B.Sowerby. Genera of Shells, April, 1822. 

 Lepas dorsalis. Ellis. Nat. Hist. Zoophytes, Tab. xv, fig. 5, 



1786. 

 Litholepas de Mont Serrat. De Blamville. Diet, des Sc. Nat., 



Plate, fig. 5, 1824. 



L. scutis terga anguste obtegentibus: carina intus con- 

 cavd : rostro, duorum aut trium squamarum subjacentium 

 latitudinem cequante : lateribus, squamarum quinque sub- 

 jacentium longitudinem cequantibus, superficie interna an- 

 guste ellipticd : pedunculi squamis superioribus verticittum 

 secundum minus duplo superanlibus. 



Scuta, narrowly overlapping the terga : carina inter- 

 nally concave : rostrum as wide as two or three of the 

 subjacent scales : latera with their internal surfaces nar- 

 rowly elliptical, as long as five of the subjacent scales : 

 upper scales of the peduncle less than twice as large as 

 those in the second whorl. 



Mandibles, with twice as many pectinations between 

 the first and second main teeth, as between the second 

 and third teeth. Maxillae without a notch, edge nearly 

 straight, and spines very numerous : caudal appendages 

 exceeding, by half, the length of the pedicel of the sixth 

 cirrus. 



Barbadoes, West Indies ; Venezuela ; Honduras ; imbedded in limestone ; 

 Mus. Brit. Cuming and Stutchbury. 



The state of preservation of the valves in different 

 specimens varies greatly ; generally only two or three, or 



