HABITS AND ECONOMY OF THE MOLLUSCA. 151 



arrangement is admirable; moreover it contains a host of species 

 collected by the numerous Trench Exploring Expeditions — 

 species very imperfectly represented elsewhere. 



Some information concerning " fancy " prices paid for shells 

 may be of interest. Scalaria pretiosa, which can now be had 

 fo/one or two dollars, was worth $100 in ITSS and $200 in 1701. 

 Fhasianella bulimoidea, which also brought $100, can now be 

 purchased at from one to two dollars, or exen less. In 1865 a 

 great English collection, that of Dennison, was sold b}^ auction, 

 in London, and some extravagant prices realized. Gypraea 

 guttata brought $200; Gypraea p7-inceps^ the same; Gonus gloria- 

 maris, also $200 ; Gonus cervus^ nearly $90 ; Gonus cedo-nulli 

 (not a very rare shell), $90 and $110 ; Gonus omaicus (also not 

 rare), $60 ; Voluta f estiva, $80 ; Oniscia Dennisoni, $90 ; Fhola- 

 domya Candida, $65 (several fine specimens in the Philadelphia 

 Collection) ; Garinaria vitrea (which Montfort stated to be 

 worth $600) brought $50. The very rare Pleurotomaria Quoyana 

 brought in Loudon, in 1872, $125. In 1876 the Raters' van 

 Lennep collection was sold, including : Voluta Junonia, $50 ; 

 3Iitra Belcheri, $40; Spondylus regius, $36, etc. For this same 

 Spondylus regius Professor Richard had previously paid several 

 thousand francs. Voluta Junonia has always been considered a 

 rare species, and dealers »have obtained as much as forty pounds 

 sterling for it. They still ask large prices for it, although a 

 number of specimens are obtained yearly by dredging or other- 

 wise, and they can generally be bought from first hands at from 

 six dollars to twelve dollars each. Gypraea umbilicata has been 

 sold for thirty pounds, and may now be had for one pound. The 

 Boston Society of Natural History possesses an Argonauta argo 

 or Paper Nautilus shell, which is said to have been purchased 

 by the gentleman who presented it to that Societ}^ for $500. It 

 is a common species, and the only reason for the great valuation 

 of this specimen, is that its diameter is about two or three 

 inches greater than any other individual known to naturalists. 



For scientific purposes common shells are quite as good as rare 

 ones, and the price demanded for a single rarity will generally 

 «ufflce for the purchase of many species of more frequent occur- 

 rence. Lovers of the beautiful are certainl}^ justified in acquiring 

 preferentially, fine specimens for their cabinets, but the too 

 frequent custom of paying high prices for presumed novelties 

 has led to much abuse in the description of new species. I 

 cannot better illustrate this fact than by citing again from Dr. 

 Grray's paper on the Cumingian Collection, published in the 

 Zoological Proceedings, London, 1867 : 



"A very large number of species in the collection have been 

 separated on very slight characters, or on the slightest variation 

 of form, state, and color. This has greatly arisen from the 



