GREGORY: FISH SKULLS 



361 



Callionymus lyra.-Th\s is one of the most curiously specialized skulls (No- 4% Brit. 

 Mus Nat Hist.) among all the hosts of teleosts. The ascending processes of the pre- 

 maxiU^ are enormous. They are received posteriorly into a deep fossa formed chiefly by 

 The laterJethmoids; the melethmoid, affected by this as well as by the dorsal shifting of 

 the huge orbits, has retreated behind the lateral ethmoids. 



mx 



A. Cottoperca gobio 



soc 



pat. 

 epiot 



B. Notothenia macrocephala 



C. Parachaenichthys 



Fig. 241. A. Cotioperca. 



B. Notothenia. C. Parachanichthys. Top views. 



Professor Starks (1923, pp. 267, 268) who drew attention to this unusual position 

 of the mesethmoid, which here simulates an orbitosphenoid, seemed inclined to place a 

 taxonomic value on this peculiar character, but it seems to be a result of the above noted 

 changes in the orbits and rostral fossa. 



The opercular apparatus is dragged backward under the influence of the pelvic suckmg- 

 disc The opercular itself is reduced almost to a vestige, its place bemg largely usurped 

 by ihe enlarged subopercular. The well-spiked preopercular is dragged backward as a 



ventral brace for this region. .^,,17 wioos. ^ A.^'^^ as 



The otolith (sagitta) of Callionymus lyra is described by Frost (IViSa, p. 455j, as 



resembling that of Labrus except in certain details. 



