THE TOBACCO BEETLE. 18 



margin of the hypostomal triangles, anteriorly adjoining submentuni, poste- 

 riorly adjoining the presternites ; occiput directed obliquely downwards and 

 forwards. Mouthparts hypognathous ; labrum and clypeus present; antenna 

 small, situated at the anterior corner of frons, separated from basal skin of 

 mandible by a narrow chitinous bridge ; maxillary palp three-jointed, no definite 

 palpiger ; submentum and mentum the conspicuous parts of the ventral side of 

 head ; maxillary articulating area simple, neither chitinized nor subdivided into 

 two or more separate lobes ; stipes labialis with well developed ligula, labial 

 palpigers, and palpi ; hypopharyngeal chitinizations not developed. Tentorial 

 bridge broad ; hypopharyngeal bracon present. Body curved, wrinkled, fleshy, 

 whitish. Legs developed ; with several joints ; last joint clawlike ; no real 

 claws ; prehypopleurum and posthypopleurum indicated but not chitinized. 

 Prothorax with small presternites fused into a narrow, transverse band ; no 

 separate prebasisternum ; no sternellum ; poststernellum well developed ; meso- 

 thorax and metathorax with well developed epipleural median lobe closely 

 connected with the alar area ; spiracle-bearing preepipleurum not reaching the 

 presternum ; no definite sternellum ; mesothorax with and metathorax without 

 poststernellum. Abdominal segments ten ; prescutal area large, protuberant ; 

 dorsal parts of scutum and scutellum not developed into ampullatory lobes ; 

 epipleurum bulged ; parasternum anteriorly limited by a straight line ; ninth 

 abdominal segment without cerci or any chitinizations. Spiracles annuliform ; 

 mesothoracic spiracle apparently prothoracic, the preepipleurum of mesothorax 

 being pushed forwards ; metathoracic spiracle rudimentary ; eight abdominal 

 spiracles. 



GENERIC CHARACTERS. 



In the family Anobiidae (Ptinidae), the genus Lasioderma, belonging to the 

 group Ptinini, is characterized as follows: Head rounded, not deeply sunk Into 

 prothorax ; epistoma strong, rigid, with median region only slightly concave, 

 and lateral regions subrectangular, projecting, not divided by any depressions; 

 labrum subrectangular, with straight anterior margin and rounded corners ; 

 clypeus somewhat broader, subrectangular ; one ocellus ; antenna two-jointed, 

 with large terminal sensory papilla ; mandible with bidentate apex and convex, 

 irregularly serrated cutting edge ; no molar part or prostheca ; maxillary 

 lacinia single, broad, flat, semiovate, spinose, extending from .distal end of 

 stipes ; at its base arising from the boundary region between hypopharynx and 

 stipes maxillaris a freely projecting, somewhat shorter, four times narrower, 

 lanceolate, spinose structure; stipes labialis broad and short; mentum some- 

 what large, transversely subrectangular, separated from the still broader, 

 trapezoidal submentum by a straight, rather faint line; maxillary articulating 

 lobe small ; gula very narrow. Legs five-jointed ; tarsal joint distinct, falci- 

 form, clawlike. Prothorax with tergum outlined like a dumbell, the alar areas 

 being lobate, much larger than the upper tergal part ; no chitinous linear im- 

 pression between alar area and the upper tergal part. Mesothorax and meta- 

 thorax both with sharply defined prescutum ; scuto-scutellar parts fused. The 

 first seven abdominal segments with a large prescutum, a narrow scutal fold, 

 and a large scutellum ; the tergal parts of the last three abdominal segments 

 not divided ; tergal folds dorsally and laterally granulated, but without trans- 

 verse series of stout, backwardly curved spinules ; tenth abdominal segment 

 well developed, with two large, cushion-like pads on each side of a linear, 

 vertical, anal fissure. Last spiracle no larger than the preceding abdominal 

 spiracles. 



