NO. 15 VAN cleave: acanthocephala 505 



anterior end of proboscis, 120 to 142 /a long on ventral surface, those on 

 dorsal somewhat shorter. One small papilla (sensory?) on each mid- 

 lateral surface of the proboscis at the level of the basal hooks and influ- 

 encing the arrangement of adjacent basal hooks as described for G. 

 lepidus. 



Lemnisci very long, in some as much as two and one-half times the 

 length of the receptacle. 



Proboscis receptacle in mature females 3.23 mm long, with brain 

 located about one third the distance from its anterior extremity. 



Testes contiguous, about 1.5 mm long. 



Mature embryos within body of female 105 to 120 /x long by 36 to 43 

 /x wn'de. 



Among some broken specimens of G. clavatus were found the terminal 

 regions of male and female in copula. This condition is so relatively 

 unusual in preserved material that a drawing of the stained whole mount 

 is shown as fig. 16 on Plate 54. 



Comparisons. Gorgorhynchus clavatus differs from G. medius in 

 that there are fewer hooks on the proboscis of G. clavatus. This applies 

 to both the number of longitudinal rows and the number in each row. 

 The largest hooks in G. clavatus are nearly twice the size of those found 

 in G. medius. The chief point of difference between G. clavatus and G. 

 lepidus is the fact that the proboscis hooks of the former are considerably 

 larger than those of G. lepidus. 



Both G. clavatus and G. lepidus have as hosts marine fishes of the 

 family Serranidae or sea basses. The host from which Linton reported 

 G. medius belongs to a genus which is placed in the family Epinephelidae 

 adjacent to the Serranidae. These forms seem to be the natural hosts of 

 members of the genus Gorgorhynchus, although Chandler (1924) found 

 this genus in Galeichthys, a marine catfish, belonging to an entirely dif- 

 ferent order of the fishes. 



Genus TEGORHYNGHUS Van Cleave, 1921 



The genus Tegorhynchus was recognized by the present author in 

 1921 to accommodate a species of acanthocephalon encountered in a 

 marine fish of Masa Tierra of the Juan Fernandez Islands off the coast 

 of Chile. As shown by Van Cleave and Lincicome (in press), this genus 

 belongs in the family Gorgorhynchidae. It is closely related to the genus 

 Illiosentis Van Cleave and Lincicome. 



