THE DEATH-WATCH AND DRUG STORE BEETLES. 863 



9 to 11-jointed; head retractile, usually protected by the thorax; 

 labrum distinct; thorax with the side pieces not separate; elytra 

 entire, with distinct epipleura? ; abdomen with five free ventral seg- 

 ments; front and middle coxa; cylindrical or sub-globose, the coxal 

 cavities rounded, open behind; hind eoxas transverse; tarsi five- 

 jointed. 



The larvEe of the Ptinidaa occur with the adults, and are white, 

 soft, grub-like creatures, covered with short, stiff hairs or bristles, 

 and when at rest lie in a curved position like the common white 

 grubs of the genus Ladun^li rua. They have six legs, but usually 

 move by drawing themselves along on their sides. Only a few spe- 

 cies, comprising those feeding upon drugs and upon the wood of 

 living trees, are economically important and injurious. The others 

 inay be classed as innoxious. 



The principal literature treating of the North American forms 

 is as follows: 



LeConte. "Prodromus of a Monograph of the Species of the 

 Tribe Anobiini, the Family Ptinida3 inhabiting North Amer- 

 ica," in Proc. Phil. Acad. Nat. Sci., 1865, 222-244. 







Fall, H. C. 'Revision of the Ptinidte of Boreal America," in 

 Trans. Amer. Ent. Soc., XXXI, 1905, 97-296. 



Casey. "Studies in the Ptinida.\ Cioidae and Sphindida? of 

 America," in Journ. N. Y. Ent, Soc., VI, 1898, 61-93. 



LeConte and Horn, in their "Classification," and Henshaw, in 

 his Check List, recognize four subfamilies of Ptinida?. Fall, in his 

 latest work, recognizes but two, viz., Ptinince and Anobiinft', rele- 

 gating the LuctiiKT to the family Cucujidas, as proposed by Maj. 

 Casey, and proposing a separate and independent family for the 

 subfamily BostricJu'mt. Sharp regards these two subfamilies as 

 forming the family Bostrichidae, and they are so recognized in the 

 present paper. 



Fall, in his Revision, records 53 genera and 259 species of 

 Ptinida 1 as belonging to the North American fauna. 



KEY TO SUBFAMILIES OF PTINIDA. 



a. Antenrue inserted upon the front of head and rather close together at 

 base; thorax without side margin. 



Subfamily I. PTININ.B, p. s<>4. 



(to. Anteume inserted on the sides of head in front of eyes and usually dis- 

 tant at base; thorax usually margined at sides. 



Subfamily II. ANOBIIN.E. p. Slid. 

 15523402] 



