208 



ALLAN HANCOCK PACIFIC EXPEDITIONS 



VOL. 5 



Genus GONODAGTYLUS Latreille, 1825 



The several forms of Gonodactylus dealt with in this paper are all 

 close allies of G. oerstedii. This species, in turn, is one of the many near 

 relatives of G. chiragra of the Indo-Pacific, with which, indeed, it was 

 identified for many years. 



Kemp's discussion'^2 of "Gonodactylus chiragra and its allies" rather 

 fully covers the difficulties one encounters in any study of the problem of 

 variation and speciation in this Gonodactylus-d\\\2Lnct. His remarks are of 

 utmost value in the description of new forms within this section of the 

 genus. 



CARINAE OF LAST 

 ABDOMINAL SOMITE 



Submediari 



Intermediate 



Lateral 



CAR.INAE OF TELSON 



Mediar\ 



latermediate 



Lateral. 



Maig^iaal 



Sabmedian 



Accessory 



ArxcKor - not aiaiays developed 



Knob 



Crest or ridcce of submediarv tooth 



TEETH OF Tt.LSON 



Lateral 



Intermediate 



Submediarv 



Fig. 25. Diagrammatic Gonodactylus telson, illustrating terms 

 used in description.''3 



72 Mem. Indian Mus., Vol. 4, No. 1, p. 150, 1913. 



■^3 The so-called anchor is not always formed and is often poorly developed ; 

 yet in some species it is unmistakably anchorlike in appearance. 



The carina running forward or anteriorly from each submedian tooth of the 

 hind margin of the telson is referred to as the crest, or ridge, of the submedian 

 tooth. 



The lobule, so called in the following descriptions, is the rounded, and some- 

 times spinule-tipped, projection intervening between the submedian and inter- 

 mediate teeth of the telson margin; it is placed at the top or apex of the sinus be- 

 tween these teeth, when this sinus is in evidence. 



The lateral tooth of the telson in many Gonodactyli is reduced in size and 

 prominence ; in others it may be obsolescent or not even indicated. It is usually re- 

 ferred to as the lateral lobe or angle rather than as a tooth, because of this reduction 

 in size. 



