( -179 ) 



tlie dorsal ridge of an Adonara individual from the ventral side; it will lie noticed 

 that the dentate part of the ridge is markedly less extended than in sarjiedon mrpedon, 

 and that the transverse fold It has not developed to a i-idge, as in f. 123 (Sumba), 

 or f. 128 (Wetter) and f. 129 (Timor). The valve of ni/o/ia/rnsis stands in shape 

 intermediate between sarpedon sarpedon and sarpedon jm/ans, the lobes being 

 slenderer than in the former, and shorter and broader than in the latter. 



The individuals from the island of Lombok approach in external characters and 

 in the genital armature still more the Indo-Malayan form. 



d. I', sarpedon /eredo/i i'rom South India and Ceylon; f. ll.j to 120, 13:!, 13-1. 

 Tlie range of this snbspecies is separated from that of sarpedon sarpedon by a 



wide area wliere most probably the species does not occnr. We have examined above 

 thirty specimens of P. sarpedon teredon from South India and Ceylon, all of which 

 are in external features and in the genital armature well distinguishable from all 

 other forms of sarpedon. 



The valve is much narrower and the sinus considerably deeper than in sarpeAon 

 sarpedon. The ventral lobe (f. 115, 133, 134) is usually slender in its apical 

 half, and curved towards the median axis of the abdomen, thus forming almost a 

 hook-like organ ; the dorsal lobe is sometimes strongly pointed (f. 133). The 

 inconstancy of the outline of the lobes is illustrated by f. 133 and 134, which are 

 taken from Ronth Imlian individuals. 



The ventral (longitudinal) portion of the valval fold extends farther towards the 

 apex of the valve than in the preceding forms, and hence the ventri-dorsal jiortion 

 has a more oblique direction. The dorsal ridge is much less raised than in sarpedon 

 sarpedon; the deuticulatiou is absent; only the middle portion of the ridge, which 

 corresponds to that part of the ridge of sarpedon sarpedon in f. 98 and IU2 which 

 bears the transverse fold or transverse ridge respectively, is elevated; it has, com- 

 bined with the transverse fold (Ji of f. 98), developed in a vertical and transverse 

 direction to a strong tooth-like transverse ridge, which slightly leans over basally 

 and dorsally. As inf. 115, taken from an examj)le from Trichopolis, the transverse 

 ridge is too inconspicuous, we give an enlarged tignre of the dorsal ridge of the same 

 specimen in the same position (f. 116), and also a figure of the organ from the 

 ventral side (f. 117). In f. 118 to 120 the transverse ridge alone is represented 

 from the apical side ; mostly the ridge is shaped as in f. 119 ; its edge is usually 

 not dentate, but there occur specimens, like that from which f. 118 (South India) 

 is taken, which have the transverse ridge dentate ; in one of the Ceylonese examjiles 

 (f. 120) the ridge is considerably smaller than in f. 110. 



The individuals which belong to the ab. f/iennodusa have no character in the 

 valve and its armature that is peculiar to them. 



In external features and in the genital armature teredon comes much closer to 

 the forms from the lesser Sunda Islands than to sarpedon .narpedon, which inhabits 

 the interjacent countries. 



e. /'. sarpedon jwjans from Sumba.; f. 121 to 12'). 



"Tin's form combines to a certain extent the characters of .sarpedon sarpedon 

 iuid sarpedon tirnorensis" and its ''genital armature resembles more that of 

 timorensis than that of sarpedon and adonarensis " (Rothschild, this volume, 

 p. 324). 



The sinus of the valve (f. 121) is deep. Tlie ventral lobe is very slender, often 



