KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 52. N:o |6. 29 
sense), which is repeated also by PELnSENEER (1911) in these words (p. 58): »Les 
espeéces de ce genre ne sont pas toutes fixées sur le cöté gauche: il existe des formes 
>inverses», fixées par le cöté droit... (dans C. pulchella RrEvE MAustralie, la fixa- 
tion se ferait indifféremment sur P'un ou Pautre cöté).» 
Through my own researches on Chama, which will be published later on, this 
view is shown to be quite unmaintainable and a subdivision of Chama as hitherto 
understood into Chama and Pseudochama corresponding to the »normal» and >»inverse»> 
Chamas has for this reason been made (see further below). 
Ch. spinosa BRoDERIP. 45 miles W. S. W., 1 sp., I. 20 mm, with soft parts 
preserved and a specimen of Pinnotheres within the shell. The specimen, which 
agrees in shape and sculpture with fig. 44 6 of RErEvE (Conch. Icon 4), was entirely 
overgrown with bryozoa but still exhibited the characteristic convexity and solidity 
of the shell, the minutely spinous sculpture, as well as, interiorly, the smooth or very 
faintly erenelated margins, the greenish gray tint and somewhat greasy lustre, as well 
as the solidity of the posterior tooth (3 b), which is separated from the very indistinct, 
nearly suppressed anterior one (3a) by an intermittent depression, while in Ch. 
reflexa both teeth are joined like a crest, which rises from the hinge plate and is 
distinetly separated by a furrow from the upper shell margin. =E. A. SMITH (1885) 
records this species from Port Jackson, and REEvE from Lord Hood's island. In 
R. M. there exist examples from the Red Sea, Madagascar and Tahiti. 
Ch. reflexa REnrvE. 42 miles W. S. W., 70—72 feet (””/s), many sps, max. h. 
48 mm; 45 miles W. S. W., 60—980 feet ("”/s), many sps, max. h. 70 mm. To this 
species I refer Ch. jukest REEVE, which proves to be merely the not full-grown (though 
mature) stages of Ch. reflexa. The ample material before me shows the complete 
transition from the smaller forms with dense and fine spines and without the two 
rows of squamulae on the hinder side of the shell, which constitute the form jukest, to 
larger specimens where the spines are more expanded and where there are two rows 
of radiating squamulae posteriorly. Also in colour may be observed this transition 
from the pale younger specimens (forma jukesi) to the more or less deeply reddish 
adult ones (the typical Ch. reflexa). 
The largest of the present specimens is marbled with red and yellow, and the 
inside of the inferior valve is violet. Two somewhat smaller specimens (max. h. 50 
mm) have retained the white colour of forma jukesi, in addition to a rosy tint on 
the umbones; the under valves are inwardly flesh-coloured in the larger, white in 
the smaller specimen. In its sculpture, consisting of dense squamulae, the larger of 
the named shells approaches Ch. multisguamosa RErvE (Conch. Icon. 4, fig. 12), 
which may perhaps be a variety of the present species. The deeper the shell is coloured, 
the stronger the animal is pigmented around and between the siphonal openings. 
There is the closest similarity between the present specimens and some shells 
from Java and from the Red Sea in the collections of the Swedish State Museum. 
The last-named form part of the collections made by M ANDREW in 1856 and 
differ only in the great solidity of their valves. Their exterior is usually much 
