206 W. S. MacLeay on the Natural Arrangement of Fishes. 



be clearh' understood, that I am asking naturalists ■whether such be 

 not the facts of the case, instead of dogmatically insisting upon it 

 that they are. I have no idea of publishing on Fishes, at least for 

 the present. 



By the way, I observe that my old friend Colonel Sykes has been descri- 

 bing a number of Indian Cyprinida; in the ' Proceedings of the Zoological 

 Societ}-.' Of course there must be " double emplois," which I hope you will 

 rectify'. I am sorry that I have not been able as yet to get any CyprinidtE 

 from our New Holland rivers ; but I attribute it to my own residence so far 

 from any river, not to the absence of them. I am promised by friends, who 

 have better opportunities, the result of their researches ; but I receive no- 

 Ihing, as they know not how to catch the minute fish of the river. However, 

 I intend to try the Nepean river myself when I go down there, which I soon 

 propose to do. In the mean time, my residence on the sea-side enables me 

 to increase my collection of marine genera, and if there be any j'ou wish for, 

 I shall be most happ}' to send them. A thousand thanks for your kind me- 

 thod of beating iij) for insects to be sent me from India. I shall be happ}' 

 to pay any fair price for the collector's time and trouble. Tell Dr. Cantor, 

 that I depend on him to increase my collection of Annulose animals, and 

 that I hope he will soon write me. Tell him also, that I have got a marine 

 serpent of the genus Pelamys, caught in the mouth of Port Jackson har- 

 bour, the only one our fishermen have ever seen. If he wishes for it, it is at 

 his service ; for he knows infinitely more of Serpents than I do, and my 

 grand desire is, to increase my collection of Annulose animals. 



But I could go on writing to you on these subjects ad infinitum, 

 and therefore I trust you will excuse any tediousness on the score 

 that my thoughts have been directed into this channel by the perusal 

 of your Monograph. Pray remember me to Dr. Cantor, Dr. Griffith, 

 Mr. Grant, and all who concern themselves with the works of na- 

 ture, believing me always, 



]\Iy dear Sir, your obliged and truly faithful, 



W. S. MacLeay. 



October 12, 1840. 



P.S. — As I have had no opportunity of forwarding the enclosed 

 letter, I sit down to make some observations on it that occur to me 

 on now reading it over some weeks after it has been \mtten. 



I know not whether you will clearly understand my meaning in 

 making the Cyclostomi the most typical of fishes. Cuvier says that 

 " the Acanthopterygii form the tj^pe most perfected by nature ;" and 

 in this I agree with him, namely, that their structure is most per- 

 fected ; but the Acanthopterygii are not therefore the most typical of 

 fishes, i. e. of a class, the general character of which is, to be the most 

 imperfectly constructed of Vertebrata. Cuvier talks much of the 

 Acanthopterygii being the most homogeneous in their variations ; but 

 are not the groups of Sharks and Cyclostomi quite as homogeneous ? 

 Nay, are not FistuJuria and Vomer more distinct from each other in 

 form than a Shark from a Skate, or a Lamprey from a Myxine ? 



There are some relations that require still to be expressed by my 

 foregoing arrangement, such for instance as that of Platycephalus 

 to Eleotris, as that of Sphyrcena to certain JSsocidce, &c. &c. Are all 



