COTTOIDS. 
175 
THE FOUR-HORNED COTTUS (sw. hornsimpan). 
COTTUS QUADRICORNIS. 
Plate VI, fig. 2, 9; Plate VII, fig. 1, (p. 
Top of the head furnished with spines and tubercles. Preopercular spines 4. Lateral line without spines. Length 
of the maxillary bones more than 2 / 5 , and of the lower jaiv more than 2 / 3 of the length of the base of the second 
dorsal fin. Least depth of the tail less titan 4 l f % of the length of the body and less than 21 % of the base of 
the anal fin. Margins of the branch iostegal membranes united by a free dermal fold, across the isthmus. 
E. bv. 5—7; D. 8 1. 9jl3 — 15 ; A. 14 1. 15; P. 15—17; 
V. 1 / 3 ; C. ,r+8 1. 9 " + x. 
Syn. Coitus scaber, tuberibus quatuor, corniformibus, in medio eapite, 
Art., Gen. Pise., p. 48; isyn. p. 77; Spec., p. 84. 
Cottas quadricornis , Lin., Mus. Ad. Frid., vol. I, p. 70, tab. 
XXXII, fig- I; Syst. Nat., ed. X, tom. I, p. 264; Retz., Fn. 
Snec. Lin., p. 328; Pall., Zoogr. Ross. As., vol. Ill, p. 127; 
Cuv., Val., Hist. Nat. Poiss., vol. IV, p. 168; Ekstr,, 
Vet.-Akad. Handl. 1831, p. 317; Nilss., Prodr. Ichth. Scand., 
p. 98; Ekstr. et Wright, Slcand. Fistc., ed. 1, p. 30, tab. 
VII, fig. 1; Kr0y., Damn. Fiske, vol. I, p. 140; Nilss., 
Skand. Fa., Fisk., p. 80; Sundev., Stockh. L. Hush.-Sallsk. 
Handl. 1855, pp. 80, 86, 178; Gthr, Cat. Brit. Mus., Fish., 
vol. II, p. 166; Loven, Ofvers. Vet.-Akad. Forh. 1862, p. 
463; Mgrn, Finl. Fisk, (disp.) p. 8; Lindstr., Gotl. Fisk. 
(1. c.), p. 14 (sep.); Ltkn, Vid. Meddel. Naturh. For. Kbhvn 
1876, p. 375; Malm, Gbgs, Boh. Fn., p. 390; Day, Fish. 
G:t Brit., Irel., vol. I, p. 49; Lillj., Sv., Norg. Fisk., vol. 
I, p. 144; M6b., Hcke, Fische d. Ostsee, p. 47. 
Cottus liexacornis , Rich., Frankl. Journ., p. 726; Fn. Bor. 
Amer., pt. Ill, p. 44. 
This species and 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 which exceed this size. The appearance 
of the Four-horned Cottus is quite peculiar, owing to 
the strongly depressed head, especially when the gill- 
covers are extended; 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 nasal 
bones farther from the eyes than in the following spe- 
cies, etc. The length of the head varies between 28 
and 33 % of that of the body. The nostrils are small: 
the two openings on each side are, as is the rule in 
the genus, fairly widely separated by the nasal bone; 
the anterior is situated nearest the snout and the po- 
sterior just 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 only slightly 
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 by 
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. These protuberances vary considerably, how- 
ever, in form and size, but without any fixed depen- 
dence on sex or age in specimens at all advanced in 
growth: during youth, however, they are 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 porous, fungiform knob. The longitu- 
dinal distance between them is greater than the trans- 
verse, the anterior pair are farther apart from each 
other than the posterior, and the space between all four 
is usually more or less rough with small, obtuse, osseous 
tubercles, which are scattered about in no regular 
arrangement. Just behind and outside the anterior 
pair we generally find a small bony spine, which varies 
in size. 
There are four projecting spines on the preoper- 
culum, all fairly large. The uppermost is the longest 
and is generally turned obliquely upwards and outwards, 
while the next is directed backwards and outwards, 
“ In young specimens there are often only 7 branched 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. 
