392 Zoological Society. 



of the head, eye, muzzle and thickness, differ notably from those 

 assigned by MM. Cuvier and Valenciennes to their P. oculata, of 

 which it wants besides the dorsal fin-spot. The ventral and caudal 

 fins are also longer. It agrees in these and other points far better 

 with P. trichopterus, P. CaroUnus, or P. guttatus {Coryphcena velifera, 

 Pallas) of these autliors, but differs from them still more widely than 

 it does from P. oculata, in the numbers of the fin-rays. 



ASTRODERMA PLUMBEUM. 



The Madeiran Astroderma recorded under the name of A. cory- 

 phanoides, Bon., (Proceed. Zool. Soc. 1840. p. 37; Trans, iii. p. 7), 

 is probably a distinct and undescribed species. It differs from MM. 

 Cuvier and Valenciennes' description of the Mediterranean fish, and 

 from that by Risso of the same, under the name of Diana semilunata, 

 in size, being only four instead of twelve or fifteen inches long ; in 

 proportions, the depth being contained three instead of not quite 

 four times in the length, making it a deeper fish, and the length of 

 the head equalling the depth ; in having the eye exactly in, not partly 

 before and altogether below the middle of the head, and the hinder 

 nostril larger than the foremost ; in the less height backwards of the 

 dorsal and anal fins, and their nearer approach at their hinder ends 

 to the root of the caudal fin. The pectoral fins are longer, and the 

 ventral fins, instead of being very short, with the first spine strong^ 

 and serrate, are half the length of the whole fish, with the first ray 

 or sjDine feeble, weak, or slender, and perfectly even or entire ; the 

 other rays, especially the first, being produced into fine hair-like 

 points. The scales are firmly fixed, not easily removeable. There 

 is no trace of the two little oblique crests or ridges at the base of the 

 caudal fin on each side the faint central keel, like those which the 

 Mackerels have ; and lastly, the pectoral and caudal fins, instead of a 

 fine coral-red, are pale tawny or dirty yellowish white; the body 

 being a dull silvery lead-colour, instead of silvery rose. 



It were not safe, from inspection of a single individual of such 

 small size, and in a genus hitherto consisting of a single species, to 

 pronounce these characters of actual specific value ; some, or perhaps 

 all, may be due merely to age or sex. The name of ^. plumbeum is 

 therefore here proposed only provisionally for the Madeiran fish. 



Ausonia Cuvieri, Risso, Hist. iii. 34'i. f. 28; Cuv. Reg. Anim. ii. 214, 



note. 

 Luvarus imperialis, (Raf.) Cuv.Reg. Anim.ii.214; Cuv. etVal.ix.412. 



I shall take an early opportunity in 'The Fishes of Madeira' of 

 furnishing a full account, with a figure from a fresh and perfect in- 

 dividual, of this little known, most rare, and interesting fish. The 

 several discrepancies between my example, which is deposited in the 

 Society's collection, and the former individuals on record, seem fairly 

 attributable to the paucitj^ of those before examined, or to imperfect 

 means of observation. The Madeiran fish differs not more from each 

 of those included in the above references than they do respectively 

 from one another, whilst it presents an assemblage of characters 

 only to be collected from them all. 



I'kis really fine and striking fish offers no ambiguities whatever 



