KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 52. N:O0O (6. 81 
and fulva the marginal teeth have the cusps of equal size, in M. responsivus a prin- 
cipal and a secondary cusp is present, and in M. rustica the latter is rather reduced 
in size and rather remote from the tooth end. 
Thalassia pudibunda (Cox). Mount Tambourine (Oct. 1912), 4 empty shells, 
Max. do 14 Mmm. 
o 5 (0 
5 25 
"Fig. 31. Teeth from the radula of Microcystis marmorata Cox. X 350. 
BedÅ a 
Fig. 32. Teeth from the radula of M. fulva n. sp. X 500. 
BBR ÅG 
Fig. 33. Teeth from the radula of M. rustica Cox. X 500. 
0 5 10 15 5 
Fig. 34. Teeth from the radula of M. responsivus HEDLEY. X 500. 
Macrochlamys suturalis n. sp. (Pl. 3, figs. 86—88; text figs. 35b, 36—38). 
Shell trochiform, thin, with slightly convex whorls and shallow margined suture; last 
whorl subangulated, not descending in front; surface finely undulatingly striated, and 
with irregular lines of growth, polished and shining. Colour fulvous, suture marked 
by a thin dark brown line, and the umbilical funnel tinted by a faint reddish hue. 
Umbilicus narrow, half covered by the columella; aperture diagonally lunate; peri- 
stome thin, inserted at an acute angle on the body whorl; outer margin rather straight, 
K. Sv. Vet. Akad. Handl. Band 32. N:o 16. ål 
