350 



HISTORY OF FISHES. 



little beauty to the ignorant are often the most 

 precious ; and those shells which an unlearned 

 spectator would stop to observe with admira- 

 tion, one accustomed to the visitation of cabi- 

 nets would pass over with disdain. These 

 collections, however, have their use ; not only 

 by exhibiting the vast variety of Nature's 

 operations, but also by exciting our curiosity 

 to the consideration of the animals that form 

 them. A mind that can find innocent enter- 

 tainment in these humble contemplations is 

 well employed; and, as we say of children, is 

 kept from doing mischief. Although there 

 may be nobler occupations than that of con- 

 sidering the convolutions of a shell, yet there 

 may be some who want the ambition to aspire 

 after such arduous pursuits ; there may be 

 some unfit for them ; there may be some who 

 find their ambition fully gratified by the 

 praise which the collectors of shells bestow 

 upon each other. Indeed, for a day or two, 

 there is no mind that a cabinet of shells 

 cannot furnish with pleasing employment. 

 " What can be more gratifying," as Pliny 

 says, 1 " than to view nature in all her irregu- 

 larities, and sporting in her variety of shells ! 

 Such a difference of colour do they exhibit ! 

 such a difference of figure ! flat, concave, long, 

 lunated, drawn round in a circle, the orbit cut 

 in two ! some are seen with a rising on the 

 back, some smooth, some wrinkled, toothed, 

 streaked, the point variously intorted, the 

 mouth pointing like a dagger, folded back, 

 bent inwards ! all these variations, and many 

 more, furnish at once novelty, elegance, and 

 speculation."* 



1 Pirn. ix. 33. 



1 Conchology, Aristotle had three orders of Testacea, 

 Univalves, Bivalves and- the Turbinated, but the 

 class itself and these divisions were loosely defined ; and 

 the same vagueness is to be found in the writings of those 

 authors who followed his method. Perhaps Dr Walter 

 Charleton, Physician in Ordinary to Charles II. was the 

 first who had a full conviction of the importance of 

 system, but his attempt to arrange the Mollusca is very 

 faulty.* The Limaces he places with apodous insects ; 

 and aquatic animals being divided as usual into the 

 sanguineous and exsanguineous, the remaining mollus- 

 cas are arranged under two classes viz. the inollia or 

 molluscula and the testacea. The first embraces all the 

 cuttles and the Lepus marinus or Aplysia ; the second 

 the shelled tribes, whose primary sections are the same 

 as those of Aristotle's, while his genera, in general 

 without definitions, rest on characters of little or no 

 value. Jean-Daniel Major, Professor of Practical 

 Medicine in the university of Keil, in the duchy of 

 Holstein, was the next to make the attempt, (1675,) 

 which is pronounced by two critics, to whose opinion 

 much deference has been shown, to be " infinitely too 

 complicated and ramifying to admit of any useful ap- 

 plication." Sibhald, Grew, Bonanni, Lister, Langius, 

 Hebenstreit, Tournefort, D'Argenville, and Klein are 

 perhaps the principal who followed in their wake, but it 

 is evident that they had all entered on their task without 

 a previous study of what the real object and use of method 



* Onomastikon Zoikon. Lond. 1671. 4to. 



With respect to the figure of shells, Aris- 

 totle has divided them into three kinds : and 

 his method is, of all others, the most conform- 

 able to nature. These are, first the univalve, 



was, what principles were to guide them in framing the 

 various sections, or what the relative bearing of these 

 divisions on one another should be. The division of 

 shells primarily into Multivalve, Bivalve, and Univalve 

 had perhaps superseded the Aristotelian, and many new 

 divisions of secondary rate were of course invented, but 

 they were arbitrary, founded on no common principle, 

 either too lax or too complex to be applicable in practice, 

 cumbersome to the memory, and clumsy in writing. 

 To analyse these methods would be wearisome and un- 

 profitable, they were next to useless when promulgated, 

 and have now no attraction even in the eyes of the pure 

 conchologist. It is when we rise from their examina- 

 tion that we are in the best mood to appreciate the 

 merits of Linnaeus. 



Linnaeus having, with a tact characteristic of his 

 genius for system, divided invertebrated animals into 

 two great classes Insecta and Hermes, was less happy 

 in his reduction of the latter into their secondary groups 

 or orders. The testaceous mollusca occupy one order by 

 themselves, in which there are four sections of equal 

 value the multivalve, bivalve (Concha,) the univalves 

 with a regular spire (Cochlea), and the univalves with- 

 out a regular spire .f In each section there are several 

 genera defined with neat precision, the characters of 

 the multivalves being derived from the position of the 

 valves of the bivalves from the number and structure 

 of the hinge-teeth, or, in the absence of these, from a part 

 influencing the opening of the valves, of the Cochlea; 

 from the unilocular or multilocular shell, but in most 

 from the formation of the aperture; while in the last 

 division the shape of the shell affords the means of dis- 

 criminating them, excepting in Teredo, which is defined 

 " T. intrusa ligno," in evident contrariety to his prin- 

 ciples and his better custom. The naked tribes are 

 placed in the order denominated " Mollusca," where 

 they stand, in " admired disorder," with radiated zoo- 

 phytes, annelidans, parasitical worms, and the Echinoder- 

 mata, which latter, however, are better in this strange 

 miscellany, than they were when they stood either 

 amongst simple or multivalved shells. 



In estimating the merits of this system it is not fair 

 to look back from our present vantage ground, and 

 magnify its defects by a comparison with modern classi- 

 fications : we are in candour to place ourselves behind 

 its author, and looking forward, say how far his efforts 

 have been useful or quickening.^ Standing thus we 

 trust to offend none of his admirers when we admit that 

 there is nothing in its principle of a novel character: 

 the soft mollusca were previously recognized and better 

 assorted by Charleton ; and every one of the sections, 

 and, if we mistake not, of the genera also, of the shelled 

 tribes, had been already recognized. It labours under 

 the censure of having too small regard to the animal, a 

 censure in some degree just, for assuredly more was 

 known of these than the definitions of the "Systema," 

 would lead us to suppose ; and it had still less regard to 

 the position of the groups in reference to their organical 

 affinities. It often associates species of dissimilar habits ; 

 and species are found in almost every genus at variance 

 with the character of this, and where consequently the 

 student ought not to have sought for them. The superi- 

 ority of it lies in its simplicity; in the regulated subor- 



t The expounders of I innaeus' system do not adopt this last 

 division, why, it is difficult to say. By disregarding: it they 

 have injured the naturalness of the method. 



t The first edition of the ' Systema Naturae,' was published 

 in 1735, but 1758 is properly the year which gave birtli to his 

 oonehological system, when the tenth edition was published. 

 It was perfected in 1766. 



