619 



MALACOLOGY. 



MALACOLOGY. 



divided into Univalves and Bivalves. The genera Patella and Cochlea 

 aeem to hare embraced all the Turbinated Univalve* ; and Cyprtsa, 

 Haliotii, and Xautiltu the Simple Univalve*. All the Bivalve* appear 

 to be collected under the term Concha; and the Atcidia, under the 

 name of Micrototmut, teem to have found a place under hia Tatarca. 



It is in the tenth edition (1758) that we first trace considerable 

 augmentation*, which increased in the last that received the correction 

 of the great Swediah naturalist'* own hand, and which appeared in 

 three volvme* : the first part of the first volume being published in 

 1766; the second part of that volume, containing the Intccta, and 

 Ytnut, in 1767 ; the second volume, containing the Plante (' Regnum 

 VegeUbile'), in 1767 ; and the third, containing the Minerals ('Regnum 

 Lapideum ') in 1768. Adanson's work wag published at Paris in 1757, 

 ten yean before the second part of the second volume of the last 

 edition of the ' Systema Nature.' But Linnaeus appears to have only 

 profited by the labours of Guettard and-Adanson to add to the 

 genera of the orders Molltuca and Tettacea of his Vcrmet, and to 

 define them more closely. Geoffrey's publication appeared nearly at 

 the same time with his own last edition. The object of Linnaeus 

 seems to have been to establish a nomenclature and form a system of 

 choochology renting on the modifications of structure in the shell 

 alone ; in net an arbitrary system, which has now generally given 

 way to systems founded upon more natural principles. 



Pallas ('Miscellanea Zoologies,' 1766) seems to have been the first 

 to point out the unsteady foundation on which the system of Linnaeus 

 rested. He shows that the subdivision of the Testaceous Molluscs, 

 a* adopted by Linnaeus and his followers, resting on the shell only, 

 without taking the animal into consideration, is far from natural ; and 

 in that spirit of prophecy which is now fulfilled, he remarks that it 

 cannot be preserved. 



Bruguiere, nevertheless, weighing the great influence which the 

 system of Linnaeus had exercised on zoology in general, and the power- 

 ful aid which it afforded to the student of that science, clung, in hia 

 ' Dictionnaire des Vers," to the method of the Swede in so many 

 points that he may be said almost to have done little more than 

 imitate him. 



Bruguiere admits the division of the two orders Molluscous Worms 

 and Testaceous Worms. The first of these he subdivides into two 

 sections, according to the presence or absence of tentacula, and conse- 

 quently jumbles together a very heterogeneoua mass of animals ; for 

 the same reason his second section is even more heterogeneous than 

 the first He however separates into a distinct order the Echini and 

 Star-Fishes. 



In the second order, or that of Testaceous Worms, though the 

 Limuean principle is kept in view, the genera are more multiplied 

 and their characters better defined ; and as Bruguiere is one of those 

 authors who has greatly contributed to the advancement of this 

 branch of zoology, we shall give an outline of his system of 



-[;:.' /v. 



He, like Linnaeus, divides the Testaceous Worms into three sections, 

 according to the number of the valves. 



In the first (Multivalves) he places the Chitons, Salanut, and 

 A not if a (Lcpaiot Linmous), Teredo, fuiulana, Pholai, Char (a new 

 and imaginary genus), Anomia, and Crania. We here have for the 

 first time a separation of the Pedunculated and Sessile types of the 

 Cirri peds (Campylotomata and Acamptwiomata) pointed out under the 

 generic appellations of Anatifa and Jialanui, and the new genera 

 FiitMlana and Crania. 



The Bivalves (second section) are divided into the regular and 

 irregular. 



Among the Regular Bivalves are three new genera, namely, Acardo, 

 Plactuta, and Perna. 



The Irregular Bivalves contain the new genera Triyonia, Pectin 

 (previously separated from the Oyster* by M tiller and Poli), Tridacna, 

 Cardila (formed at the expense of Chama, Linn.), and Terebratula, 

 containing a division of Atiomui. 



The Univalve* are subdivided into the Unilocular, or those without 

 any partitions, and the Multilocular, or those which are furnished 

 with regular partions or septs. 



The Unilocular Univalves without a regular spire contain Patella 

 and fumrcila, divided for the first time, and, notwithstanding the 

 observations of Pallas, Dentalium, Strpula, Siliquaria, and Aiper- 

 yiUtim, among others ; PinurtUa, SUiqwtria, and Aiperffillum, being 

 MW. 



The Unilocular Univalves with a regular ipire present a leia hetero- 

 geneoux assemblage. We find among them Vuluta reduced to a more 

 uniform genus by withdrawing from it some of the widely different 

 iipecie* which Linnaeus had congregated under that name, and the 

 following new geuena : Orula (or rather OrtUum), (Hira, Purptu-a, 

 Cauit, Terebra, futui, Ceritltium, Bulimia, Planorbit, and Natica. 



The Multilocular Univalves not noticed by Linntcus, but pointed 

 out by Breyn or Breyniu* of Danxig, in hi* ' Disertttio do Poly- 

 thalamiU, nova Teitaceorum Claiae' (1732), comprise the genera 

 Camtrima, Ammmita, and Ortkoctrat, at the expense of the genus 

 ffamliltu of Linnteu*. 



Gmclin, whose edition of Linnaeus appeared about the same time 

 with the work of Bruguiere, requires but little notice. Four or five 

 MW genera wet* added to the ' Systema Natures,' which received in 



this edition a great number of species, too many of them added care- 

 lessly and in a manner to create confusion, instead of dissipating it 



In 1791 Poli published the first volume of his splendid work, 

 ' Testacea utriusque Sicilito eorumque Historia et Anatome.' Of the 

 care with which the details are wrought out, and the magnificence 

 and accuracy with which they are illustrated, it is impossible to speak 

 too highly. But while Poli avoids the errors of those who sought to 

 establish a system of testaceous molluscs on the structure of the 

 shell alone, he runs into the opposite extreme, and rests hi* arrange- 

 ment on the soft parts of the animal only, without any reference to 

 the hard part or shell He divides the Molliuca into three orders : 

 1, Mollusca Brachiata (Fepift, 4c., of Linnaeus, and the Tritons and 

 Serpulcc of the same author). 2, Mollusca Reptantia (Gastropods of 

 the more modern authors). 3, Mollusca Subailientia (Multivalves and 

 Bivalves of the old school, and characterised as being provided with a 

 long foot, as being fixed to rocks or free, and as always wanting a head 

 and eyes). 



Of these families the most natural are the Bivalves, and their arrange- 

 ment is based upon the structure of important parts. 



Little seem* to have been done for the science from 1789 to 1798, 

 a period which included the French revolution and its reign of terror ; 

 but in 1798 a new era commenced, and George Cuvier published his 

 'Tableau Elerneutaire de 1'Histoire Naturelle des Animaux.' This 

 great man, clearly perceiving that Guettard, Adanson, Geoffrey, Miiller, 

 and Poli took a right view of the principles of classification when they 

 proposed ,the organisation of the uaimal aa its basis, adopted that 

 method, and united, a* Pallas had done, under the name of Mollutca 

 both the Vermct (Mvlliuca) and Vermet (Teitacca) of Liumcus. Consi- 

 dering the absence or presence of a shell as a contingency of secondary 

 importance, he divided the Mollusca into three sections, the Cephalo- 

 podous Molluica, the Gastropodous Molliuca, and the Acephalous 

 Mollusca. finally he arranged this ' Second Grand Division of the 

 Animal Kingdom ' in six classes, and gave the following method in 

 his last edition of the 'Itegne Animal' (1S30). 



Class I. CEPHALOPODA. 



1, Sepia of Linnams, containing the following genera and subgeuera : 

 Octoput, Polypus, Eledone, Argonauta, HclUrophon, Loliyo, Loligoptit, 

 Onycliolcuthis, Sepiota, Sepioteuthit, and the Cuttles properly so called, 

 namely, Sepia of Lamarck. 2, Nautilus of Liunteus, containing 

 Spirula, the Nautili properly so called (Nautilus pompiliut, &c.), 

 Lititui, Ifortolui, And Orthoceroi. 3, Selemnitet, including Actino- 

 comox ( ?)*. [CEPHALOPODA.] 4, Ammonitci, including the Ammonites 

 properly BO called (Simplegodet of De Montfort), Planita of De Haau, 

 Ceratitet, Orbulites, Globitet, Goniatilel, Pelagut, Scapkitet, llacuiitct 

 (Tirantics, JUiabditet, fcMyotarcolita), Uamilet, Turrilitet (the last 

 with M. Audouin's doubt). 5, Camcrina (Nummulilet of Lamarck), 

 with their infinity of genera. [FOIIAMIXIFERA.] 



Class II. PTEROPODA. 



1, Clio. 2, Cymbulia. 3, Pneumodcrmon. 4, Limacina. 5, Jfyalcea. 

 6, Cleodora, including Cretea, Cuvieria, Ptyche, and Eurybia, of M. 

 Rang, and perhaps Triptera of Quoy and Gaimord. 7, Pyrgo (fossil). 



Class IIL GASTEROPODA. 



Order 1. Pulmonifcra. 



Section 1. Pulmonifera Terratria. 



1, Umax, including Limax properly so called. Arion. Vaginulut. 

 TataceUa and ParmaceUa. 2, Helix, including Helix properly so 

 called, Vitrina (Helicolimax of Ferussao). Bulimia. Pupa. Chan- 

 drut, and Succinea. 3, Claiuilia. 4, Acltatina (including Polyphcmut 

 of De Moutfort). 



Section 2. Pulmonifera Aytatica. 



1, Onchidium. 2, Planorbit. 3, Limncnu, or Limnaa. 4, Phyta, 

 near which Cuvier would place Scarabtu of De Montfort. 6, Auricula 

 (including Carychium of De Fdrussac). 7, Jfelamptu (Conovulia, Lam.). 



Order 2. Nudibranchiata. 

 1, Dorit. 2, Onchidori*. 3, Ptocamocerot. 4. Polycera. 5, Trilonia. 



6, Thethyt, or Tethyi. 7, Scyllaa. 8, Giaucut. 9, Laniogci-us. 10, 

 Eolidia. 11, Carolina. 12, Flabellina. 13, Tcryipet. 14, liiuiru. 

 16, Placobrancbui. 



Order 3. fnfcrobranchiata. 

 1, Phyllidia. 2, Diphyllidia. 



Order 4. Tectibranchiala. 



1, Pleurotrancliui. 2, Plcurobranchtca (Pltumliranchidium of De 

 Hlniuville). 3, Aplysia. 4, Dolabdla. 6, Notarchiu. 6, Bur* 



7, Aktra, including Bulfaa, JiuUa, and the Akcr& properly so c.illi d 



'mm of Meckel, and Lobaria of De Blainville). 8, Qaitropteron. 

 9, Umbrella. 



Order 5. Heteropoda (Lam.). 



These were all comprised by Forskal under hi* genus Plcrolrachea, 

 and comprehended 



* In the toil Actinncomax 1 Included In the ncotion appropriated to the genus 

 Itclrmniltt, though it is upokon of as a Rcnus. In the 'Table Mctliodiquo,' 

 Actirwcomax it printed as genns, not a tub-genus. 



