26 BULLETIN 03, UXTTED STATES NATIONAL MUSEUM. 



It is to be noted that Escherich, in his paper on the internal male 

 organs of beetles, notes that those of the Carabida^ illustrate the 

 simplest, most primitive condition. Packard figures Bhfps as inter^ 

 mediate between the Carabida? and Hydrophilus." 



Sculpturing. — From simple punctures the sculpturing passes 

 through the different degrees of modification to distinct murication 

 or tuberculation, or as in a few species to distinct hairiness with com- 

 paratively simple punctures. 



From a careful study of the sculpturing under high power in the 

 species of the Kleodimi, I have observed the following: 



A simple puncture is a more or less rounded depression, variable in 

 size and depth, aud bounded by a more or less distinct, although 

 fine wall or margin; from the floor of this depression arises a minute 

 hair or seta, which scarcely passes beyond the mouth of the punc- 

 ture. The surface with such a punctuation is smooth. 



Anj^ modification will affect the puncture in one of two ways: 

 Either by a hypertrophy of its margin or by an increased growth or 

 hypertroph}^ of the hair-like process. In the first instance the hair 

 may remain small or atrophic; in the second the hair-like process 

 is alone affected. Some punctures may become completely aborted. 



The hair-like process arising from the hjqDodermis may develop 

 into a soft, flexil)le hair, or by a slightly increased chitinization of its 

 cuticle into a bristle or seta, and by still greater increased chitiniza- 

 tion, with or without hypertrophy, into a spinule or spine. 



In the muricate type of sculpturing the anterior lip of a puncture 

 is thickened and more or less produced into a blunt or acute point; 

 from the sides of this prominence the margins gradually diminish 

 so that the posterior boundary of the puncture will be but slightly 

 modified; the thickened edge is directed upw^ard and backward, 

 chiefly the lattei-; the hair or seta may be aborted, renuiin small, or 

 become more chitinous to become a seta, and be carried upward by 

 the hyper(ro]jhie(l margin to project from the ])osterior surface of 

 the more ])i<)minent anterior margin of the puncture. 



When the mai'gin of the puncture is equal and nnu^h thickened a 

 tubercle is formed, which varies in size from a granule to a well 

 mai'ked and rotuided eminence; the j^uncture may be entirely closed 

 or obliterated, or may still be evident as a minute [)oi'e-like depressicm 

 with a correspondingly small hair or seta j^rojecting from it, and 

 from some i)()int, usually the posterior wall of the tubercle. There 

 are all the intermediate degrees of variation to be observed. 



The ])unctures ma}^ remain simple and the hair become long and 

 flexible. 



If the anterioi- lip of the puncture becomes minutely nuiricate the 

 sculpturing is more or less asperate. 



«Text-Ii(.()k Kilt., p. -I'.M, lif,'. -tcr., .4, H. jiiul ('. 



