COTTOIDS. 



175 



THE FOUR-HORNED COTTUS (sw. iroiiNsiMPA>i). 

 COTTUS QUADRICOKNIS. 



Plate' VI, lig. 2, V; I'late VII, tig. 1, cf- 



Tdj) <if tlic head finiiishcd /rill/ s2)iHes ai/d tid/crcle.'^. Preopercidar spines 4. Lalci/d lii/c /ritliaid spii/es. Lci/rjtii 



of file ii/<(.iilhiri/ l/diifs more tlian ^/.,, ai/d of the In/rer jair more than ^/., of the lei/r/fh of the t/ase of the second 



dorsal fi/. Least dejdh of the tail less than 4^'^ % of the length of the l/od/j ond less thai/ 21 % of tl/c l/ase of 



the anat fin. Marijii/s of the t/ranehiostefpd mcinl/rai/es united, t/i/ <i free denn/d fold across the islhinns. 



/,'. Ar. 5— 7; J>. « 1. ill:!— If); .1. 14 1.15: P. l,j — 17; 

 V. ',;,; ('. .!• + « 1. !•" + ,)•. 



Si/ii. Cottiis scaber, tiibf;i-ibiis i[iiatu()r, eoriiiforiiiibus, in medio capite, 

 Art., Gen. Pise, p. 4-8; Hyii. p. 77; Spec, p. 84. 



('nttits quadricornis, Lin., Mus. Ad. Frid., vol. I, p. 70, tab. 

 XXXII, fig. 4; Sj/st. Nat., ed. X, toni. I, p. 2(;4; Rktz., Fii. 

 8uec. Lin., p. 328; Pall., Zoogr. Boss. As., vtil. Ill, p. 127; 

 Cuv., Val., Hist. Nat. Poiss., vol. IV, p. Ili8; Ekste,, 

 Vet.-Akad. Haiidl. 1831, p. .-JH; Nilss., Prodi: h-lith. Scand., 

 p. 98; Ekstr. et Wright, Skand. Fish., ed. 1, p. 30, tab. 

 VII, fig. 1; Kroy., Danm. Fiske, vol. I, p. 140; Nilss., 

 Skand. Fa., F/sk., p. 80; Sundev., Stoekh. L. Ilush.-Sallsk. 

 Handl. 1855, pp. 80, 80, 178; Gthr, Cat. Brit. iMiis., F/,5/i., 

 vol. II, p. ICIi; LovKN, Ofvers. Vet.-Akad. Forh. 1862, p. 

 403; Mgrn, Finl. Fisk. (disp.) p. 8; Lindstr., Gotl. Fisk. 

 (1. c), p. 14 (sep.); Ltk.v, Vid. Meddel. Naturh. For. Kbhvn 

 1870, p. 375; Malm, Gb,js, Boh. Fn., p. 390; Day, Fish. 

 G:t Brit., Irc'L, vol. I, p. 40; Lillj., Su., Norg. Fisk., vol. 

 I, p. 144; MOi!., HcKE, Fische d. Ostsee, p. 47. 



Coitus hexacornis, Rich., Frankl. Journ., p. 720; Fn. Bor. 

 Ainer., pt. Ill, p. 44. 



This species ;uid the following one are the largest 

 of the Scandinavian Cotti, and in Sweden they attain 

 about the same size, generally about 250 mm., but 

 one may occasionally meet with specimens of the Four- 

 horned Cottus wliich e.xceed this size. The appearance 

 of the Four-horned Cottus is (juite peculiar, owing to 

 the strongly depressed head, especially when the gill- 

 covers are e.xtended; the small eyes, with the breadth 

 of the interorbital space in large specimens greater than 

 the longitudinal diameter of the eye, but in small ones 

 considerably less; the less distinct projection of the 

 upper orbital margin, in consequence of which the inter- 

 orbital space is almost flat; the flatter and more elon- 

 gated snout, which removes the spines of the two nai?al 

 bones farther from the eyes than in the folloAving spe- 

 cies, etc. The length (jf the head varies between 28 

 and 33 % of that of the bodv. The nostrils are small: 



the two openings on each side are, as is the I'uli' in 

 the genus, fairlj^ widely separated by the n;isal ])()iie; 

 the anterior is situated nearest the snout and tlic po- 

 sterior ju.st in front of the anterior margin of the eye; 

 both open into cylindrical or funnel-shaped dermal 

 tubes. The two lateral ridges on the top of the head, 

 which run from the eyes to the occiput, are onh' slighth- 

 marked as low, rounded bars. The four spines which 

 in the other Cotti mark the beginning and the end of 

 these ridges, are generally replaced in this species b-\- 

 singular structures, which rise in the form of spongeous 

 bony protuberances, two in front, each on the upper 

 posterior margin of the orbit, and two behind on the 

 occiput. Tliese protuberances vary considerabh', how- 

 ever, in form and size, but without any fixed depen- 

 dence on sex or age in specimens at all advanced in 

 groAvth: during youth, however, they ai'e very indistinct. 

 As a rule, the two anterior ones are the largest, and 

 the two posterior are sometimes much worn or even 

 wanting. They consist of a thin, foliate, osseous disk, 

 which is somewhat bent and at the upper margin wi- 

 dens out into a ))orous, finigiforni knob. The longitu- 

 dinal distance Ijetween them is greater tlian the trans- 

 verse, the anterior pair are farther apart from each 

 other than tlie posterior, and the space betAveen all four 

 is usually more or less rough with small, obtuse, osseous 

 tubercles, which are scattered about in no reffular 

 arrangement. Just behind and outside the anterior 

 pair we generally find a small bony spine, which varies 

 in size. 



There are four projecting sjjines on the preoper- 

 culum, all fairh- large. The uppermost is the longest 

 and is generally turned obliquelv upwards and outwards, 

 while the next is directed backwards and outwards. 



" In young specimens there are often only 7 brauelied rays in the caudal fin; sometimes none of these rays is branched, as is the 

 case in a specimen from Siberia, 137 mm. in length. 



