I 



BY E. W. FERGUSON. 235 



tiuct, being: broken up and coniused by tlie tubercles, it is not an 

 easy matter to determine tlie interstices upon wliich the tubercles 

 are situated, in the teniale specimens, which 1 refer to M. ohsole- 

 tus, the elytral stria3 are more easily traced. From a study of this 

 species, 1 believe that the relation of tlie rows of tubercles to the 

 interstices is as follows : the lirst and second rows are situated on 

 the second and third interstices respectively, the third row on tlic 

 sixth interstice, the fourth row on the seventh; the fourth inter- 

 stice is devoid of tubercles generally if iiot always; the fifth is re- 

 presented by the humeral tubercle, and, perhaps, by one or two 

 isolated ones, but these are not ])i-esent in all species, and, in some, 

 may possibly occur on tlie fourth. The derm between the tubercles, 

 apart from the seriate punctures, is generally smooth; in some, 

 however, it is moi'e or less asperate. The apex of tlie elytra, in 

 both sexes, is flanged by a row of strong tul)ercles, wliicli, in tlie 

 male, do not reach to tlie middle line, the apical margin, however, 

 not being emarginate at tlie suture; in the female, the tubercles 

 extend practically to the suture, tlie innermost being strongly pro- 

 duced, mucroniform, sometimes conjoined with its fellow of the 

 opposite side, sometimes separated by a dee[) emargination. The 

 undersurface is smooth and Itcvigate in all, exce})t M. Boisdurali, 

 in wliich it is more opaque, and closely setigerous. The prosternum 

 bears a pair of mammary-like i^rojections, situated in front of tlie 

 middle coxa?; but in M. Boisdiivali these are obsolescent. The ventral 

 segments are transversely convex, more markedly so in the female. 

 The basal segment is depressed hi the male, and the apical seg- 

 ment generally has an ill-detined, transversely oval impression at 

 apex. In M. Boisduvali, the segments are more flattened. The 

 anterior tiliia' bear a few small granules or denticles \aryiiig in 

 position and of specific importance; the posterior tibiae have a 

 strong excavation immediately above the apex, and on the inner 

 surface of the tibiti?, but this is absent in .1/. Boisrhn-ali. A speci- 

 men of J/. Scliihih'rrl was dissected, to examine the male sexual 

 organs. The penis, or the chitinous portion of it, is very large, and 

 the free extremity })icornuate. The forceps aie rein-esented by 

 two, small, triangular, chitinous pieces, moi'o <»r less closely con- 



