250 GEO. H. HORN, M. D. 



PoGONiSTES. — Thorax cordate; form elongate, parallel. Elytra 

 with feeble basal luargiual line and scutellar stria. Dorsal punctures 

 as in Po(jonus. 



DiPLOOHiETUS. — Form of Pogonistea, thorax not narrowed at base, 

 Prosternum broadly sulcate. Scutellar stria absent; basal marginal 

 line obliterated at niidille, forming at the humeri a moderately elevated 

 recurved carina; striae obliterated at base. Two dorsal punctures only^ 

 one median on the outer side, the other one-fourth from the apex on 

 the inner side of the third interval. 



Our species are as follows : 

 Pogoiilis texanus, did., Rev. Mag. Zool., 1868, p. 64; Annales Belg. XIV., 



p. 31. 

 P. {Pogonistes) , planatus, = depreisus, \\ Lee, Trans. Am. Ent. Soc, 1874, 



p. 44. 

 P. (Diplochoetus), L<econtei, = paraUelus, || Lee, loc. cit. 



The name Jepressus is preoccupied in any case, whether the genus 

 Pogonistes be adopted or not; paraUelus is used already in Pogonus, 

 and should the genus I) I'l) loch set us be adopted, may be allowed to 

 remain The latter species should be compared with P. rutilus, Chev., 

 Am. Fr., 1878, p 197, it is possible that they may be identical. 



(g. h. II.) 



DYTISCID^. 



The discovery of Anodochilns exiguus, (Aube), in Florida, has given 

 us the means of determining the fact that the genus indicated by 

 Babington must be suppressed, and the presence or absence of the 

 mentum tooth has very little value. 



Iljydrojjorus plicipenni's, Crotch, \ii misplaced in the synopsis. Its 

 position should be near exiguus in the group with basal thoracic and 

 elytral plica. 



In this section the sculpture of the metasternum, whether sulcate 

 or not. will aflbrd the means of grouping the species. The groov- 

 ing of the metasternum is very much more common than Crotch 

 supposed. 



Dijtistus hitissimus, Linn., should not be included in our lists. 

 I am satisfied that the species was never alive on this side of the 

 Atlantic, and from the number of specimens sent me from time to 

 time for determination, identical with those of England and pinned 

 on English pins, I am convinced that there must be either great 

 carelessness or deception on some side. We have enough species 

 legitimately introduced and now acclimated without bringing dead 

 ones on pins. («■ U- H.) 



