48 EEOTYLHm 



and probably several others described by Lacordaire are in the same position. Crotch 

 in his revision [Cist. Ent. i. p. 450] mentions eleven species which he considered to be 

 synonymous. I feel that no scientific advantage is gaiaed by recording these species 

 as distinct, but in some cases I have not seen sufficient specimens to enable me to 

 corroborate his opinion or otherwise. 



2. Mycotretus nigropunctatus. 



Erotylus nigropunctatus, Duponeh. Monogr. Erotyl. p. 22, t. 2. f. 34 \ 

 Erotylus puncticollis, Duponeh. Monogr. Erotyl. p. 25, t. 2. f. 43 2 . 

 Mycotretus nigropunctatus (Dej.), Lac. Monogr. Erotyl. p. 142 3 . 



Eab. Costa Kica, Volcan de Irazu (Bogers). — Brazil l 2 , Rio Janeiro 3 . 



In this species (if indeed it can be treated as distinct from M. ornatus) the 

 tridentate mark has disappeared from the base of the thorax, and all the black marks 

 tend to disappear, the last to go being the four transverse spots of the thorax and two 

 spots on the elytra below the shoulders. Lacordaire mentions four varieties, but it is 

 difficult to find two specimens entirely alike. One of our specimens from Irazu has 

 the four thoracic spots, the three elytral spots, and black scutellum; in the other 

 the four thoracic spots are very faint, the others are absent from the elytra, and the 

 scutellum is yellow. 



The legs in the two specimens from Irazu before me vary, being clouded and with 

 fuscous tarsi in the more maculate example, and entirely yellow in the other. 



3. Mycotretus tigrinus. (Tab. III. fig. 9.) 



Erotylus tigrinus, Oliv. Enc. Meth., Ins. vi. p. 437 x ; Ent. v. p. 485, t. 3. f . 40 ; Duponeh. Monogr. 



Erotyl. p. 22, t. 2. f. 35 2 . 

 Mycotretus tigrinus, Lac. Monogr. Erotyl. p. 145 3 ; Crotch, Cist. Ent. i. p. 451 \ 



Eab. Mexico, Toxpam (Salle); Guatemala, San Geronimo (Champion). — Guiana, 

 Surinam 1 3 , Cayenne 4 ; Brazil 2 ; Amazons 4 . 



The present insect affords an instance of the uncertainty of using the form of the 

 mentum as a sectional character: Crotch differs from Lacordaire in regarding it as 

 " rounded in front." On examination it appears to me formed just as in M. ornatus, 

 but the angles of the pentagonal raised portion apparently are a little less sharp. The 

 striae are not at all gemellate in any specimens I have seen. It is a variable species, 

 the spots on each elytron and even on each side of the thorax not being symmetrical ; 

 but in our specimens, including one from Mexico, the spots are fewer and larger than 

 in a typical one from Cayenne (Beiche), and those on the thorax are placed regularly, 

 four in front in a square, three near the base, and two externally near the front angles. 

 The scutellum is black in the San Geronimo specimens, but I do not think there is 

 ground for considering these distinctions of specific value. The abdominal lines are 



