THE DEATH-WATCH AND DRl'O STOKE BEETLES. 



885 



Tribe VI. PTIL1XIXI. 



This tribe is composed of a single genus, seperated from those 

 preceding mainly by the characters given in the tribal key. The 

 head is deflexed, less retractile than in the preceding group; an- 

 tennae 11-jointed, serrate in female and branched in male 



XTX. Ptilinus Geoff. 1764. (Gr., "feather.") 



Small cylindrical species, covered with short, fine appressed 

 pubescence. The antennae of male have the third joint elongate- 

 cylindrical, with a basal process as long as the joint itself, and 

 joints 4 to 10 strongly nabellate or with long flat processes folding 

 like a fan; tarsi as long as the tibiae, with the first joint as long 

 as the two or three following. Two species have been taken in In- 

 diana, while another probably occurs. 



KEY TO INDIANA SPECIES OF PTIULNUS. 



a. Side margin of thorax tine but well defined and even throughout; sub- 

 apical transverse carina of last ventral segment distinct. 



1G82. RUFieoBNis. 



a a. Side margin of thorax irregularly granulate-serrate and not well de- 

 nned; subapieal ventral carina nearly or entirely wanting. 

 b. Thorax equal to the elytra in width: branch of fourth antennal joint 

 of male scarcely three times the length of joint : scutellum elongate, 

 finely and densely rugose. lobatus. 

 1)1). Thorax a little narrower than elytra : branch of fourth joint nearly 

 rive times the length of joint: scutellum quadrate, coarsely rugose. 



16S3. peuixosus. 



1G82 (5332). Ptilixus ruficorxis Say. Jonrn. Phil. Acad. Nat. Sci.. III. 

 1823. 186 ; ibid. II. 110. 

 Cylindrical, elytra not wider than thorax. Black or piceous. opaque, 

 usually paler in female; antenna} and legs reddish-yellow, thighs often 

 darker. Branch of fourth joint of male antenme six or seven times the 

 length of joint. Thorax slightly wider than elytra, widest before the base, 

 sides broadly curved, hind angles rounded, front ones rectangular, front 

 margin rather strongly rounded, narrowly refiexed at middle ; surface finely 

 grannlose at base, more coarsely in apical half ; median line feebly im- 

 pressed, terminating at base in a feeble, smooth protuberance. Elytra a 

 little more than twice as long as thorax and a little less than twice as long 

 as wide, finely scabrous and rather closely and distinctly punctured. Length 

 3-4.5 mm. 



Throughout the State: frequent. May 11-December 25. Oc- 

 curs on dead branches of oak and maple, into which the larvae bore. 



P. lobatus Casey, dark pieeo-castaneous. antenna? paler, length 

 3-5 mm., is recorded from Ohio. 



