240 SUPPLEMENT. 
11 (4). Plateros infernus. 
Ater; prothorace subnitido, lateribus late rufis angulis posticis acutis, disco ad marginem anticam subrugose 
punctato haud carinato, basi obsolete canaliculato, in medio parum elevato, haud emarginato ; elytris 
equaliter punctato-striatis, versus apicem leviter ampliatis; antennis sat longis, articulis quarto ad 
undecimum duplo fere longis quam latis. Long. 63-72 millim. ¢ Q. 
Hab. Panama, Volcan de Chiriqui, Bugaba (Champion). 
The species of this group are extremely difficult to separate, and unless the structure 
of the disc of the prothorax is studied together with the proportion of the joints of the 
antenne, as well as the general facies, it is almost a hopeless task. In the present 
species the thorax is short and small in the male, wider and with more produced hind 
angles in the female. The absence of a carina in front of the thorax, the longer 
antenne, the duller elytra (which are more widened behind than in most of its allies) 
will distinguish it from P. canaliculatus, Say, which it resembles in its black elytra, with 
scarcely any trace of a shoulder-stripe. From P. terminalis, to which it is closely allied 
in the thoracic sculpture, the more expanded elytra and black apical joint of the antenne 
will most readily separate it. A good many specimens were taken by Mr. Champion. 
11 (s). Plateros erebus. 
Ater, subnitidus ; prothorace nitido profunde sulcato, lateribus angustius rufis, angulis posticis subrectis ; elytris 
subparallelis, versus apicem vix expansis, interstitiis altcrnis elevatioribus ; humero parum elevato tenuiter 
testaceo; antennarum articulis intermedio latiusculis, subquadratis. Long. 6-67 millim. 
Hab. Gvatemara, Cerro Zunil (Champion); PayamMa, Bugaba (Champion). 
Chiefly separated from P. terminalis on account of the black antenne. It is often 
as small as P. striatus; the quadrate thorax, with a deep straight sulcus extending 
frequently to near the front from the base, will best distinguish it. Taken abundantly 
at Bugaba, Chiriqui. 
Plateros striatus (p. 22). 
Var. To the localities given, add :—Panama, Volcan de Chiriqui, Bugaba (Champion). 
Taken abundantly at an altitude of 83500 to 4000 feet. The thorax has acute hind 
angles, narrows towards the front, and has a short basal fovea with a transverse ridge 
on each side. 
Plateros flavicollis (p. 23). 
To the localities given, add :—Panama, Volcan de Chiriqui (Champion). 
Occurs with P. striatus, but much less commonly. 
14 (a). Plateros carbonarius. 
Aterrimus; prothorace quam elytra angustiore, subnitido tenuiter piceo-marginato, disco inequaliter obsolete 
canaliculato, antice subrugoso punctato ; antennis leviter serratis, articulo secundo parvo, tertio brevi, 
