of the Sub-family Pclidnotinm. 271 



sternal very short, much comin-essed, and vertical in front : 5th ventral 

 segment long ; nietasternum flat. 2 . Unknown. 



The peculiar form of the hind tibipe will readily dis- 

 tinguish this from any form of Pclidnota, 



31. Arroivi, n. sp. 



$, Elongate, moderately convex, above entirely dark bronzed- 

 green, shining : head — especially the clypeus — closely and coarsely 

 rugose-punctate, the vertex sparsely punctured : thorax widest at 

 the middle, thence a little sinuately narrowed to the hind angles, 

 which are not acute nor outwardly directed ; front angles prominent 

 and acute ; side margins i-eflexed ; the surface broken — especially 

 near tlie sides — by shallow depressions ; moderately closely punctured 

 on the disc, much more closely at the sides, the punctures rather 

 large: scutellum punctured : elytravery gradually widened to beyond 

 the middle, distinctly transversely ridged at the base, rather strongly 

 rugose-punctate, the punctures becoming seriate near the sides ; 

 humeral and apical calli smooth : pygidium finely and closely 

 aciculate-rugulose, the extreme apex smooth, thinly clothed with fine 

 decumbent hairs, and sparsely setose at sides and apex : under-side 

 and legs metallic-green ; tarsi shining black : metasternum entirely, 

 and abdomen at the sides, pilose : the latter smooth and shining down 

 the middle, the last segment glabrous : antenui-e brown. 



Long. 25 mm. Lat. 12-5 mm. 



Hob. Ecuador (Guayaquil). 



[This genus is constituted for the above species and 

 Peiidnota cylindrica, Waterh., the only known forms 

 exhibiting the peculiar excision of the posterior tibiae at 

 the base, with which character is associated an exception- 

 ally narrow cylindrical form. As each is known only by 

 a single male specimen, the generic diagnosis may not 

 be adequate for distinguishing the female, in which the 

 tibia may be expected to be of the normal type. The 

 differences between Mccojpelidnota Arroivi and cylindrica 

 are very slight, and until additional specimens can be 

 compared their value must remain rather uncertain. The 

 type of the new form however is considerably smaller 

 than that of M. cylindrica, which was brought from 

 Guatemala, the head especially being relatively less broad. 

 The clypeus is distinctly less transverse and the mandibles 

 are more strongly bilobed. The thorax, on the contrary, 

 is rather more transverse and its sides are more strongly 



TRANS. ENT. SOC. LOND. 1904. — PART II. (JUNE) 18 



