MOLLUSC A. 
501 
the limule is formed by the left valve only ; psendolitna (Lam,), much more 
rarely white than pink; nodosum (Mont.) is perhaps noi—rosettm (Lam.), 
ov pundattmi (Brocchi), or scabrum (Phil.); exigumn {Gm^l.^^istdlatum 
(Reeve) ; ruhrum (Reeve) = fasciatum (Mont.) ; suecicum (Lov^n) is distinct 
from minimum (Phil.) ; edule (L.), to its 'varieties belong also lamarckii 
(Reeve), halticum (Beck, Reeve), and rusticum (Chemn. not L.) ; californiense 
—pseudofossile (Reeve), very near to ciliatum (Fabr.) ; muricatum of 
Chemnitz and other authors perhaps muricatum oi JArmi ) Jlavum (L.) 
= rugosum (Lam.) ; procerum (Sow.), a variety of it is laticostatum (Sow.) ; 
coronatum (Spengler) (Reeve); radiatum (Reeve) seems to be 
a variety of tenuicostalum (Lam.); hullatum of authors perhaps Solcn 
lidlatus of Linn<5; ringiculum (Sow.) comes from the West Indies; rugatum 
((Axowov.^^apcrtum (Chemn.); mxdicum {\\i^QVQ)=^jjapyraceum (Sow.) = 
japonicum (Bunker) ; norvegicum (Spengl.)=/^^^;(^a^^<m of Pennant not Linn6 
=vitellinum ) pennanti and ohlongum of Reeve to be distinguished from the 
Mediterranean {Q\\emn.)=.Jlavum {Boiri) — stdcatum (Lam,); ele- 
ncnse (Sow.) and oviptdamcn (Reeve) shortly characterized; Iccvigatum of 
Reeve is probably not that of Linnd, and may bo called glabratum ; pecii- 
natum (L.) probably v^oi—molicum (Born) ; grbnlandicum (Chemn.), the 
young of it is horeah (Reeve) ; medium of Linn^ is probably that of Chem- 
nitz and other authors ; tumoriferum of Reeve is not that of Lamarck ; 
guichardi (Bernardi) from New Caledonia briefly described; donaciforme 
(Spengl.), a variety of it is australicme (Reeve) ; subretusmn (Sow., Reeve) 
is only a variety of retusum (L.), but auricula (Forsk.) is a distinct species. 
E. Rdmer, Mai. Blatt. xv. pp. 85-99. 
Tridacnacea. 
Tridacna gigas, eloxigata, squamosa, crocea, and serrifera, Kiister, Conch, 
sect. 66, pp. 3-7, pis. 1 & 2, 
Ilippopus maculatus, Kiister, ibid. p. 8, pi. 3. 
MYTILACEA, Cuv. (Lucinacea, Ad.). 
Kelliid^e. 
Montacxda tumidida and donacina (Se. Wood) dredged among the Shetland 
Islands. JefFr. Ann. & Mag. Nat. Hist. 18G8, ii. p. 299. 
A bivalve mollusk, the shell of which is stated to be entirely enclosed in 
the mantle, found on Holothurise in the Philippines by Dr. 0. Semper. 
Reisen in den Philippinen, vol. i. Holothurien, p. 99. 
GALEOMMIDiE. 
Thyreopsis, g. n. Testa sequivalvis, sequilateralis, trigono-ovata, aperta ; 
margins dorsali convexo, ad umbones subacuto. Cardo edentulus, ligamento 
interne sub umbonibus instructus. Th. coralliophila, sp. n., Mamitius. II. 
Adams, Proc. Zool. Soc. 1808, p. 14, pi. 4. fig. 8. 
Unionid^e. 
XJnio. The monograph of this genus is continued by Sowerby in Reeve’s 
Conchologia Iconica, parts 208-273, pis. 01-84. — Several observations and 
corrections concerning the North- American species treated of in this mono- 
graph are given by G. Tryon, Am. Journ. Conch, iv. pp. 106 & 283. 
