240 



SCANDINAVIAN FISHES. 



Fam. GOBIIDiE. 



Body elongated, terete or with the caudal part compressed, head sometimes depressed. Dorsal fin-formation re- 

 gular, continuous or divided into two fins, with the anterior p>art or fin shorter than the jwsterior and consisting 

 of flexihle, simple rays". Anal fin in structure and extent analogous to the soft-rayed imrt of the dorsal fin or 

 the posterior dorsal fin. Ventral fins with 6 (seldom 5) clearly distinct rays, the outermost being simple, the 

 inner ones branched, and the innermost {hindmost) ones usually the longest. Pseudobranchice present, but some- 

 times only rudimentary. Number of rertebrce from 27 to 29. Air-bladder and pyloric appendages generally 

 wanting. No osseous connexion bet/reen the suborbital ring and the preoperculam. 



This family, as established by Gunther'', is one I sufficiently marked to have given rise to the establish- 



of those containing the greatest number of species 

 — about 500 are entered in the system — even though 

 future researches may show, as seems highlj- probable, 

 that many of these species are really only nominal. 

 The variations of form within the family are also 



ment of several subfamilies — Gunther'' adopts four — 

 two of which are represented in the Scandinavian fauna. 

 Here, however, we may follow Richardson and Blee- 

 KER in treating the one of these subfamilies as a di- 

 stinct family. 



Subfamily G B 1 1 N iE. 



Ventral fins set close together. Vertical fins distinct. Gill-openings lateral. 



The greater part, about 450, of the species be- 

 longing to the famil}' range themselves in this subfamily. 

 In a great number of them, about 100 species, corre- 

 sponding chiefly to Bleeker's Eleotriformes, the ventral 

 fins are indeed set close together, but are entirely or 

 at least partly separate from each other. Some of these 

 fishes, the genera Periophthahms and Boleophthalmus, are 

 of especial interest on account of their singular manner 

 of life, which, like that of the ■well-knoAvn Climbing-fish 

 {Anahas), displays at its highest the capability of fishes 

 of adapting themselves to circumstances foreign to 

 their nature. These two genera belong to the Tropics, 

 where they live between high and low water-mark or 

 in fresh Avater near the sea. But water is hardly their 

 true element, for they are generally found on land, 

 where thej^, generally at least, seek their food. Their 

 relatively narrow gill-openings enable them to sustain 

 life for a long time in the air, and their pectoral fins 

 are brachiate and fleshy at the base, being thus trans- 



formed into organs of creeping oi- hopping. The eyes, 

 which project from their sockets, are protected by a 

 dermal fold, a kind of lid. Such is their equipment 

 for the life they lead, hopping about on clayey or muddy 

 ground in chase of insects or crustaceans, or even 

 leaping up on the branches of trees or the roots of the 

 mangrove. Sometimes they may be seen in shoals, 

 tumbling about or hopping, as if in sport, on the 

 muddy ground, and at the approach of danger burying 

 themselves in the mud, or seeking shelter in a hole 

 burrowed by a crab or a crevice between the stones. 

 Even Osbeck has described this singular phase of pisc- 

 ine life". 



The nucleus of the subfamily, the greater part of 

 Bleeker's Gobiiformes, on the other hand, consists of 

 the forms Avhich have the ventral fins united by a 

 membrane into a funnel-shaped instrument of adhesion. 

 To this division belong all the species of this subfamily 

 that occur within the limits of the Scandinavian fauna. 



" As a rule, tliis part of the ilorsal fin-formation is sliorter in tlie female tliaii in tlie male, and in one of the Scandinavian species 

 it is wanting in the females. 



* Cat. Brit. Mus., Fish., vol. Ill, p. 1. 



' Bleeker (Arch. Neerl. So. Ex. Nat., tome IX (1874), pp. 280 etc.) has an entirely different determination for his four subfamilies; 

 but (as well as Gill: Smiths. Misc. Coll., No. 247, p. G) he also ranges Vallionymus and Platijptera in two distinct families. 



"^ Ostindisk liesa, p. 130. Cf. also Dussumier in Cuv., Val., Hist. Nat. Foiss., vol. 12, p. 186, and Pechuel-Loesche in Breijm's 

 Thierleben, Bd. 8, p. 12.^. 



