40 ' Psyche [April 



Described from numerous specimens taken at Madeira Mamore 

 Railroad Company Camp, No. 41, 306 kilometers from San Anto- 

 nio, State of Matto Grosso, nesting with Dolichoderus as described 

 above. 



The typical affinis differs from mayi in its larger size 

 (length 12 mm.), coarser sculpture, which is transverse on disc 

 of pronotum; absence of long hairs on the epinotum and on ver- 

 tex, and black abdomen, ^'ar. mayi is intermediate between 

 the typical affinis and the small Central American variety pan- 

 amaensis Forel. 



Named after Mr. May, senior member of the firm now building 

 the Madeira Mamor' Railroad Cowit|ia%y. 



Dolichoderus (Monads) debilis var. rufescens, var. nov. 



Worker. Length 3h mm. Head excluding mandibles, behind nearly as broad 

 as long, subcordate; eyes small, convex, a little posterior to middle of head; cly- 

 peus convex, anterior margin straight; mandibles short and thick; antennae long, 

 scape extending | its length past occiput; funicular joints sub-equal, except api- 

 cal, which is I5 times the length of preceding joint. Pronotum convex, broader 

 than long, sides rounded without margin; spines short, acuminate, directed for- 

 ward and outward, the distance between tips as great as width of head at base. 

 Mesonotum convex; meso-epinotal impression very pronounced. Epinotum with 

 sub-equal base and declivity; base feebly convex, seen from above rectangular, 

 somewhat longer than broad, its lateral and especially its posterior borders strongly 

 marginate; declivity arcuately excavated. Petiole broad, lamelliform, compressed 

 anteriorly, its anterior surface flattened below and convex above, its apex with a 

 minute tooth. Gaster broadly elliptical, about the length of thorax. Legs rather 

 long. 



Head and thorax sub-opaque with coarse shallow punctures, which are less 

 numerous on the front of the former, and finer and more indistinct on the prono- 

 tum. Pleurae longitudinally regulose. Mandibles rather shining, sparsely punc- 

 tate. Petiole and gaster shining, very finely striolate and sparsely and finely 

 punctate. 



Hairs pale yellow, suberect on the gaster, clypeus and thoracic dorsum, fine and 

 obhque on the antennae and legs. 



Color ferruginous red, mandibular teeth black, tibiae slightly infuscated. 



Female. Length 5 mm. Resembling the worker. Ocelli small. Pronotum 

 3^ times as broad as its length at middle, without spines. Mesonotum convex in 

 front, more flattened behind. Epinotum rounded, without trace of margin, its 

 base convex, about half as long as the concave declivity. Petiole as in worker. 

 Gaster more elongate. 



Sculpture similar to that of the worker, but the punctation of the head and 

 thorax is somewhat coarser. 



