MALACOLOGY. 



corrections of the old system. These new lights fur- 

 nished by Guettard may probably have determined 

 d'Argenville to publish, in 1757, a nevr edition of his 

 Conchology, adding a great number of badly executed 

 plates of animals, under the name of Zoomorphoses. 



In the same year Adatison applied Guettard's 

 system in a much more extended point of view in his 

 account of a Voyage to Senegal, naming, with great 

 precision, all the external parts of the animal as well 

 as those of its envelop, and drawing very philosophical 

 conclusions on the relative connexion between them 

 both ; but, unfortunately for science, he only applied 

 his arrangement to the shells of Senegal, and did not 

 attempt to form a system generally upon that basis. 



Another French naturalist, Geoffroy, profiting from 

 the same hints thrown out by Guettard, and so ably 

 seconded by Adanson, in his description of the terres- 

 trial and fluviatile molluscs in the environs of Paris, 

 1766, gave an admirable definition of the animals 

 as characteristic of the arrangement of their shells. 



Miiller, the celebrated author of the Fauna Danica, 

 was the first zoological writer who adopted a similar 

 principle in his description of terrestrial and aquatic 

 worms ; his system, although more complete than 

 that of Geoffroy, is still very unnatural, and inferior 

 to that of Adanson. 



It is about this period that a change in Linnacus's 

 Systema Naturae, with regard to molluscous animals, 

 became obviously necessary. In the nine editions of 

 that work, he had not named the molluscs at all, the 

 naked animals we now so designate being distributed 

 as worms in his class of the Zoojrfiytes; and such as 

 were covered with a shell furnishing his third order of 

 the same class, under the name of Testacece ; but in his 

 tenth edition, great augmentations were made ; and 

 in the twelfth, which may be considered the last that 

 underwent the revision of that great man, many more 

 were added. This, was published in the years 1766, 

 7, and 8 ; and it is to be remarked, ten years after the 

 hints of Adanson had been thrown out, by which 

 Linnaeus doubtless benefited, he, nevertheless, in the 

 characters of his genera confined himself to mentioning 

 an analogous mollusc ; and if the work of Adanson 

 materially affected his system, it was only then exhi- 

 bited by an alteration in his genera of shells, properly 

 so called, without leading to any positive confession 

 of the knowledge of their inhabitants being essentially 

 necessary to his arranement. The impulse given 

 throughout Europe by the labours of Linnaeus, 

 seconded to a great extent by the writings of Buffon, 

 occasioned several naturalists to publish anatomical 

 descriptions of molluscous animals. 



Fabricius, Miiller, and others may be cited, and, in 

 in order to disturb as little as possible the long esta- 

 blished school, every effort was made to reconcile the 

 organisation of the animal with its covering. 



Pallas may therefore be considered the founder of 

 a new school, and of that new systematic arrangement 

 which has progressively gone on in improvement till 

 it now is acknowledged to be the best and the most 

 natural. In his Miscellania Zoologica, 1766, he proves 

 that Linmeus in the arrangement of his molluscous 

 worms, had wandered widely from nature. That his sub- 

 divisions of shells, as admitted by the naturalists of 

 liis day, could not stand ; in consequence of his having 

 considered their configuration only, without a refe- 

 rence to the animal, he therefore proposed to unite 

 the two as forming a more natural order. 



Brnguicre, an author of modern times, who has 



contributed more largely than any other to the science 

 of niiilacology up to that period, does not, however, 

 appear to have reaped all the advantages he should 

 have done from the labour of his predecessors, and 

 though he has made some very necessary changes, 

 he, for the most part, was contented tq follow their 

 general principles. 



Gmelin, who published an edition of the Systema 

 Natura of Linnaeus in 1789, which was about the 

 time of Bruguiere's writing on the subject of worms 

 in the French Encyclopaedia, although he had an 

 opportunity of consulting all the newly-broached ideas 

 on the subject, has scarcely varied in any very im- 

 portant feature from the twelfth edition of Linnaeus. 



But in 1791, the celebrated Italian physician and 

 anatomist Poli, was the first to publish the genera of 

 molluscs according to the organisation of their struc- 

 ture without any reference to their testaceous covering, 

 which up to that period had only been partially effected 

 in some genera ; no one previously possessing either 

 nerve or talent enough to propose such a plan as 

 generally applicable to every similar creature ; but he 

 only confined his researches to the molluscs of the 

 two Sicilies ; he there divides the animals into three 

 orders ; under the name of Mollusca brachiata, he 

 characterises all such as have numerous arms, in- 

 cluding consequently the Sepia of Linnaeus ; in the 

 second order, Mollusca reptantia, all such as possess 

 the faculty of climbing by means of a large foot, and 

 having a head and eyes like the common sail, and 

 most of the univalves ; and thirdly, the Mollusca subsi- 

 Icntia, including such of the molluscs as possess a large 

 foot by which they are affixed or not, to rocks and sub- 

 marine bodies, but constantly devoid of a head or eyes. 

 This order included the bivalves and multivalves. 



Thus, down to 1796, the science of malacology had 

 been making progressive steps towards its present 

 state, aided, as we have before stated, by the labours 

 of other eminent naturalists in all parts of Europe ; 

 but as they had only worked upon the system of 

 those we have shortly mentioned, they merely as it 

 were assisted in navigating more easily the old 

 vessel, without venturing upon a new model for them- 

 selves. From 1789 down to 1798, a period of nearly 

 ten years, the science of malacology appears to have 

 remained nearly stationary. 



Cuvier, whose scientific labours, though fettered, 

 had never been subdued by the convulsed state of 

 political occurrences, then appeared on the stage, 

 and commenced the foundation of the prodigious 

 improvements he has since accomplished. Justly 

 feeling, with those naturalists who had preceded 

 him, that a natural and methodical arrangement 

 might be effected of molluscous animals, upon the 

 same principles as those which guided all other na- 

 tural productions, namely, the study of their organic 

 structure, he proposed the classification which now 

 is received as the nearest perfection, by being the 

 most closely drawn from Nature's precepts. He first 

 of all imagined that molluscous animals should be 

 placed a degree higher in the scale of creation than 

 they had previously occupied, and precede those ani- 

 mals which were externally articulated, though inter- 

 nally without hard parts, such as insects. The next 

 innovation on long established custom was, upon the 

 suggestion of Pallas, to unite definitely under the 

 classical name of molluscs, the Linnaean molluscous 

 order of worms, with the testaceous order ; considering 

 the existence or absence of a calcareous covering as 



