The Male Genital Armature of the Dermaptera. 445 



Sub-family 4. LANDlciNiE. 



Antennae 12-15 segmentis, clavatis; prosternum postice con- 

 strictum ; mesosternurn postice rotunclatum ; metasternum in 

 lobum subrotundatum productum ; manubrium parallelum, duplo 

 longius quam latius, rectangulare ; metaparameres longissimi, 

 angusti, subparalleli, symettrici ; virga longa, gracilis, haud 

 spiralis ; preputials laminis chitinosis instructus. 



Antenna? with 12 to 15 segments, the third long and cylindrical, 

 the rest strongly clavate ; prosternum subparallel, constricted 

 posteriorly ; mesosternurn rounded posteriorly ; metasternum pro- 

 duced into a more or less rounded lobe ; manubrium parallel- 

 sided, rectangular, about twice as long as broad ; metaparameres 

 very long and narrow, asymmetrical ; virga very long and slender ; 

 preputial sacs with chitin-plates ; tarsi slender, third segment 

 about half as lon^ as the first. 



Genus Landex g. n. 



This genus is erected for " Psalis " femoralis Dohrn, from 

 Southern India and Ceylon, and probably the Malayan P. plebeja 

 Dohrn will fall here too. The former may be taken as the type ; 

 the manubrium is peculiar, recalling that of Labidura riparia, but 

 much longer ; the genital armature is quite peculiar ; the meta- 

 parameres are unusually long and narrow, curved at the tips, and 

 asymmetrically curved, in a manuer recalling the forceps of Aniso- 

 labis maritima ; the virga is long and slender, and simple, with no 

 spiral structure, rather broad in the basal third ; its entire length 

 is about double that of the preputial sack, which is armed with a 

 leg-shaped chitin-plate (PI. IX. fig. 11). 



This armature does not resemble that of any other species 

 known to me; in the form of the manubrium,* Landex differs 

 sharply from the Psalinee, and in the genitalia it differs from 

 everything else ; the manubrium is suggestive of relationship with 

 Labidura, in which genus Dohrn originally placed it. The presence 

 of chitin complex plates in the preputial sac is suggestive of an 

 approach towards the Labiidse, as also the narrowness and asym- 

 metry of the metaparameres. 



The ninth sternite of the male of Landex femoralis has a 

 prominent keel, produced into a sharp point, which seems hitherto 

 to have been overlooked. 



* Trans. Ent. Soc. London, 1915, p. 271. pi. xxxi. fig. 15. 



Oct. 20th, 191-' 2 i 



