KUNGL. SV. VET, AKADEMIENS HANDLINGAR. BAND 52. N:o [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. d. 14 mm. 
(é) Ss 10 
15 95 
Fig. 31. Teeth from the radula of Microcystis marmorata Cox. X 350. 
BUG A 4 
Fig. 32. Teeth from the radula of M. fulva n. sp- X 500. 
BGR Ad: 
Fig. 33. Teeth from the radula of M. rustica Cox. X 500. 
° 5 10 5 - 
Fig 34. Teeth from the radula of M. responsivus Hepiry. X 500, 
Macrochlamys suturalis n. sp. (PI. 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 52, N:o 16 11 
