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Show 64 ZOOLOGY OF TilE VOYAGE OF TilE BE.AGLE. I t bottom is rounded and rather exceeds a right angle; a readily felt than seen: the ang e a t t the post;rior edge of the orbit : the ascending vertical from the angle would ford~ a tal~gletnl .o ards a little below the middle. The opercle · · t 't straight ben mg s 1g 1 Y mw marg.m tI S no qm e . ' bt le and shows some indication of two very minute teriorly m a very o use ang ' termma es pos . t b d the membrane: from the lowermost of d . t b'ch however do not proJeC eyon flattene pom s, w 1 . • ' b 1 asses obliquely forwards to form a continuous curve h . t the margm of the su opere e p . . t "ethse tpho mt sf the interopercle wh I.C I . t 1 bly well developed. Gill-opemng of moderate Size: 1 IS o era fi d WI a 0 the branchi. al membrane, wb 'I.C h apparen tl y has only four rays, has a shallowh n.o tchh in ront, an 'd t th other without being attached to t e 1st mus. 8 continuously from one s1 e 0 e • . . . d passeT he lateral h.n e commences a t the upper angle of the opercle, and, mclmmg upwda r s, fr uhn s h d II. e which can hardly be distinguished, but to the upper e ge o t e Parallel not to t e orsa m h If. h t' d th dorsal fi' n t.t s di. stance l~r om wh I' C h · tained about three times and a a m t e en tre ep ; IS con h k . f tl . . 't l'ttle before the termination of t11at fin. Cranium, snout, c ee s, p1eces o 1e Jt termma es a I d 11 1 t' 1 fins covered with finely ciliated scales; those on the 1 the body an a t 1e ver Jca ' . . opere e, d ' II b t those on the opercle and body large; the latter arranged m obhque crown an snout sma ' u . d I d b t f' t rows. about twenty-seven m· a 1o ngl· t u dina! line from the gill to the cau a, an a ou ouhr eehn m. a v' erb·c al one fJ.O m t 1le d orsa1 t o the ventral line : a scale taken f.r om the row beneda' t t . e lateral li·n e and about t 1le ml' ddle of the body' is of an oblong form, .1 ts brIe adtdh exIc ee mgt e1dts len th, with the free edge dotted and finely ciliated, ~he basal margm rat 1er eep y crena , theg crenations separated by seven stJ·ire, which are camed on for only a short way, and do not converge to a .r.a n. The 1·5 cales on the dorsal and anal fins are small and closely compacted; • • • • • d' t' t those on t h e tio rmer arrange d Obliquely , but the line of obhqmty 1s m the opposite 1rec 10n o what it is on the body. . The dorsal fin commences in a line with the posterior angle of t~e o~ercle, and ~ccup1es a n· h If the entire length· the height of tl1e spinous portwn 1s nearly umform, but space equa mg a · b · !'ttl · d sl ightly iucreases backwards; between the tips of the _s pine~, the mem ra~e 1s a I e Ja~ge : the soft portion is scarcely more than one-third the spmous m length, but IS somewhat h1gher, terminating upwards in an acute angle; the longest of the soft rays is about .half the depth of the body, the dorsal fin itself not included. The anal answers to the sof: por~10n of the dorsal, which it exactly resembles; it has two spines in front,_ the. first ~f whtch IS very short, an~ scarcely more than one-third the length of the second, wh1ch 1tself IS shorter th.an th~ soft rays, the second spine is stouter than any of the dorsal spines. These two fins term mate ~~ the sat~e vertical line. The caudal appea1·s to have been square, but the rays are wom at ~he bps, so that its exact form cannot be asrertained; It is coated with scales for four-fifths of 1ts l engt~ from the base. Between the dorsal and the caudal fins is a space equalling not quite one-th1~d the depth of the body. Pectorals attached a little behind the opercle, and a little below the m1ddle; slightly pointed; about the length of the head or rather shorter; the fir~t ray only half the length of the second; fourth and fifth longest; all the rays, with the exceptwn of the first two aml the last two or three, branched. Ventrals attached a little further back than the pectorals; the first soft ray prolonged into a filament reaching to the commencement of the anal ; the spine is about half the length of the filamentous ray, and about two-tl~irds t~at of the seco~d soft ray. Between these fins is an oval lanceolate scale about one-tlmd the1r length; and m their axillre another elongated one, narrower and more pointed than the former, and rather exceeding it in length. FISH. 6.5 B. 4; D. 12Jl6; A. 2/12; C. 1.'>, and 4 short; P. 21 ; V. 1/5. Length 3 inches. CoLoun.-Not noticed in the recent state. In spirits, the whole fish, tins included, appears of a uniform dark brown. Habitat, Porto Praya, Cape Verde Islands. The only specimen of this new genus which exists in the collection was taken by Mr. Darwin off Quail Island, in the bay of Porto Praya. It is small, but proJ.ably full-sized, or nearly so ; since the greater part of the species of Pomacentrus, to which genus it is so strongly allied, average about the same dimensions. Possibly some of the generic characters, which I have given above, may prove hereafter to be merely specific ; but till other species shall have been discovered, their exact value cannot be ascertaiued. FAMILY.-SCOMBRIDJE. GENus-P AROPSIS. Jen. Corpus altum, t·ltomboideum, valde compressum, squamis minutissimis obtectum. L~'nea lateralis antice sursum paulo arcuata, per totam longitudinem inermis. Cauda lateribus /laud carinatis. Dentes in ~ttraque maxilld uuiseriati, tenuissimi, acuti; in lingua, vomere, et palatinis, velutini brevissimi. Ape1·tura brancltialis amplissima, membrana decem-radiata. SpinaJ quinque liberce loco pinnce dorsalis primaJ; spind minuta p1·ceeunte t·eclinata antrorsum jlexa. Dorsalis secunda, aJque ac analis, continua, sine pinnulis falsis; ante analem spinaJ duce liberce. Pectorales parvaJ. Ventrales nullce. Caudalis profundefurcata, lobis acuminatis, subelongatis. This new genus belongs to that section of the ScombridaJ characterized by having a number of short free spines, instead of a first dorsal fin. It is most neat·ly allied to Lichia, especially to the L. glaucus, which it resembles in general form, as well as in many of its particular characters. It has the same reclined spine in front of those which represent the first dorsa!, and the same two free spines in front of the anal ; also the same form of opercle; the same deeplyforked caudal, and small pectorals. But it may be at once distinguished from that genus by the absence of ventrals, of which there is not the least trace : the body is also deeper, rhomboidal rather than oval, and more compressed. In all these respects it agrees better with Strornateus, which would seem particularly to meet it in those species, such as the S. candidus and S. securifer, which are represented by Cuvier and Valenciennes as having a number of minute truncated K |