LITHOTRYA VALENTIANA. 371 



anterior ramus), and the nine terminal ones on the usual 

 structure. Third cirrus, the anterior ramus, with the 

 five basal segments, thick and paved, and eleven terminal 

 segments on the usual structure : posterior ramus, with 

 one basal segment paved, and sixteen other segments on 

 the usual structure. In the posterior rami, however, of 

 both the second and third cirri, it is difficult to draw any 

 distinct line between the paved segments and the others. 

 Caudal Appendages, short, either just exceeding in 

 length the pedicels of the sixth cirrus, or equalling only 

 the lower segment : segments flattened, cylindrical, six in 

 number, there being, in the same individual, twenty- one 

 segments in both rami of the sixth cirrus. 



6. LlTHOTRYA VALENTIANA. PI. VIII, fig. 5. 



Conchotrya Valentiana. /. E. Gray. Annals of Philosoph., 

 vol. x (new series), 1825. 



L. scutis in profundam tergorum plicam insertis : tergo- 

 rum opposito superior e margine, plica altera deque prof undd 

 instructo : carina crista prominente centrali, marginibus 

 quadratis, in parte superior e : rostro rudimentali : late- 

 rib us et pedunculo ignotis. 



Scuta locked into a deep fold in the terga ; the latter 

 having a second equally deep fold on the opposite upper 

 margin. Carina with a prominent, central, square-edged 

 ridge in the upper part : rostrum rudimentary. Latera 

 and peduncle unknown. 



Animal unknown. 



"Red Sea, imbedded in an oyster-shell. British Museum. 



General Bemarh. — The two specimens in the British 

 Museum are small, and in an imperfect condition, without 

 the peduncle or the latera, and without the body of the 

 animal. The capitulum so closely resembles that of 

 L truncata, that it is quite superfluous to do more than 



