AMERICAN COMPONENTS OF THE TENTYRIIN^ 397 



ica for a short distance beyond the Isthmus of Panama, and the 

 type described above under the name godmani, agrees with Mr. 

 Champion's description, except that the lateral lobes of the front 

 are described as diverging ; they are in no sense everted in the 

 specimen described above, but have their external sides inter- 

 nally rounding anteriorly; comnitinis Champ., is a closely allied 

 species and I have another still smaller, represented by two spec- 

 imens from Espirito-Santo, Brazil. The singular cephalic char- 

 acters of bicavtceps and alveolatmn may possibly relate only to 

 the females of the cufreus type, to which they evidently belong. 

 £ptt?'agomay represented in our fauna at present by a single 

 species, includes also the Mexican E-pitragus chevrolati and 

 possibly 2i\sopilosiis, of Champion ; it seems to be purely Sonoran 

 in habitat. The left antenna in the unique type of uintammi 

 becomes gradually pale testaceous toward tip, the right antenna 

 being black throughout, — a singular malformation. In aher- 

 rans there is a feeble modification of the apical part of the pro- 

 thorax, reminding us of the male of the next genus, but this 

 cannot be regarded as a transitional character ; it is related to 

 nietallicus^ which is out of place in the arrangement of the 

 "Biologia," but differs in the much more transverse prothorax.^ 



^ Since this was written I have received from Mr. Champion, good series of 

 examples of forms related to metalUcus and cufreus, from various points in Mex- 

 ico and Central America. These specimens shed much light on the difficulties 

 and uncertainties attending generic delimitation in this part of the Epitragini, 

 for it is quite evident that the females of some of the closely allied forms of the 

 metalUcus group, have pronotal characters similar in form to those of Bothrotes, 

 although so feeble in development as to indicate that these characters in Lobo- 

 metopon may simply be atavistic or reversional in nature. One of the chief 

 peculiarities of Lobometopon consists in the acutely and gradually pointed form 

 of the body posteriorly ; this is as well developed in the metalUcus group as in the 

 more t\'pical species and, even though some females of that group have two feeble 

 pronotal ridges and a very slightly thickened lateral margin, it is to be noted 

 that these ridges never extend to the apical margin or interrupt the continuity of 

 the latter as they do in Bothrotes. I am therefore of the opinion that the metal- 

 Ucus group cannot be held to unite the genera Lobometopon and Bothrotes. The 

 specimens of the cupreus group before me show rather conclusively that the ex- 

 cavation behind each eye, alluded to in the above table, is a sexual character 

 affecting the female. Attending this character we have finer and denser punc- 

 tures of the head and of the pronotum, especially toward the apex and sides of 

 the latter. There are a good many species belonging to both the metalUcus and 

 cupreus groups, but the material sent me seems to show that those made known 

 in the present paper are distinct from those described by Mr. Champion in the 

 " Biologia." 



