COTTOIDS. 
173 
THE ALPINE BULLHEAD (sw. bergsimpan"). 
COTTUS POECILOPUS. 
Fig. 50. 
Head armed as in the preceding species , but the uppermost preopercular spine not so curved , sometimes almost 
straight. Distance between the anal fin and the tip of the snout at most % of the length of the body , and 
the length of the base of this fin more than 50 % h of this distance. Length of the innermost ray of the ventral 
fins less than half , or even than a third of the length of the fins. Gill-openings as in the preceding species , 
and also the relative length of the jaws. 
Fig. 50. 
Cottas poecilopus from Motala River, 1st Oct., 1861, C. Sundevall. 
Natural size. 
R. br. 6 C ; D. 7 1. 8^/17 e 1. 18; A. 14/; P. 13 1. 14; V. */ 4 ; 
C. x + 7 — 9+,r; L. lat. sajpiss. imperf. 
•* 
Syn. Cottas poecilopus , Heck., Ann. Wien. Mus., II (1836), p. 
145, tab. 8, fig. 1 et 2; Sund., Ofvers. Vet.-Akad. Forh. 
1851, p. 185; Nilss., Slcand. Fn ., Fisk., p. 67; Heck., 
Kn., Silsswasserf. Oesterr., p. 31; G-thr, Cat. Brit. Mas., 
Fish., vol. II, p. 157; Jeitt., Arch. p. 1. Zoologia, vol. 
I, p. 175; Lindstr., Gotl. Fisk., 1. c., p. 14 (sep.) ; Coll., 
Forh. Vid. Selsk. Chrnia 1874, Tilla:gsh., p. 24; 1879, 
No. 1, p. 12; Or.SSON, Ofvers. Vet.-Akad. Forh. 1875, No. 
3, p. 129; Malm, Gigs, Boh. Fn., 388; Lillj., Sv., Norg. 
Fiskar , vol. I, p. 131. 
Cottas gobio , Day, Fish. G:t Brit., Irel., vol. I, tab. XIX, 
fig. 2. 
Obs. X T one of the Scandinavian species of this genus has been 
so variously estimated, and justly so, as the Alpine Bullhead in its 
relation to the preceding one. Most of the characters given by 
Heckel can scarcely be retained, and only one of them — that which 
consists in the length of the innermost ray of the ventral fins, a point 
not touched upon by Heckel in his latest work — may be regarded 
as au unmistakable mark of the species, as far as we know it up to 
the present. Furthermore, Malm, Day, Benecke and Mobics and 
Heincke still maintain the opinion that the two species are not di- 
stinct. On examining the different relations of age and sex in both 
species (see the appended table), we also find that their relative po- 
sitions in the chain of development indicate a common origin of a 
period not far removed from the present. In all the respects in which 
Cottas poecilopus differs from Cottas gobio, it exhibits the juvenile 
or the male characters of the latter, or both combined. This appears 
most clearly from a comparison between the length of the ventral 
fins and the distance from the anal fin to the tip of the snout, for 
the relative size of the fins gradually diminishes with age — pro- 
vided that this be expressed by the increase in the length of the 
body — and is greatest in the males and greater in Cottas poeci- 
lopus than in Cottas gobio. It is also strange that, while in Cottus 
gobio the females are more common than the males, the contrary is 
the case in Cottus poccilopms , at least in the collections of the Royal 
Museum. Again, in the south and east of Sweden at least, no fixed 
limits can be set to the range of either species: Sundevall found 
both in the island-belt of Stockholm, they occur together in Mo- 
tala River, and LikdstrSm assigns them both to Gothland, even though 
it be to different lakes. It is, therefore, easy to understand how 
confusion has often arisen in the specific and sexual differences of 
the two species. The following comparative table may afford more 
minute information on this point. 
a Lilljeborg, 1. c. 
6 At least 53 % in the specimens we have measured. 
c Sometimes 5, according to Heckel. 
d Or 9, according to Heckel. 
e Or 16, according to Heckel. 
/ Or 13, according to Heckel. 
