MORSE: OBSERVATIONS ON LAMELLIBRANCHS. 171 
work; as infusoria devoured the ciliated epithelium the rigid 
framework was revealed. The transverse bars were not aligned, 
the rods became very attenuated at the edge of the gill, and were 
Fig. 26. — Turtonia minuta (Fabricius). 
bent inward. I hope to make a further study of the animal. 
The creature showed no timidity and with a needle I removed 
flocculent matter from the gill cavity without causing any con- 
traction of the shell. 
CARDIUM PINNULATUM Conrad. 
Fig. 27. LengtK, 1.3 mm. 
The syphons are very short extending only slightly beyond the 
edge of the shell. Anal syphon represented by the valve which is 
most delicate, a row of brown dots encircling it. The branchial 
syphon is fringed with long and short papillae distinctly alternat- 
ing. A few longer papillae are seen springing from the base of 
the syphon and just within the posterior margin of the shell the 
papillae become long tentacles, nearly all recurved and in some 
