76 CASEY 



and foveiform laterally, also with deeply impressed, finely, densely 

 punctate and puberulent green areola;, which become obsolete in about 

 inner half, except posteriorly, where they extend to the suture through 

 small in size; intervalspunctureless; under surface closely, coarsely and 

 irregularly sculptured, the sterna broadly smooth along the middle, 

 the first ventral narrowly and deeply sulcate; legs bronzed, the femora 

 with a feebly rose-colored reflection apically. Length 22.0 mm.; 

 width 8.5 mm. Panama (Taboga Island) *insularis n. sp. 



Some of the above species, notably those of the valens series, appear 

 to resemble the Mexican drummondi Lap.-Gory, in general form and 

 sculpture, but the lEigure of that species seems to indicate a broader 

 and more arcuate basal pronotal impression, and, as our forms consti- 

 tute several allied species, I assume that none of them is actually 

 synonymous with drummondi. It is impossible to imagine any reason 

 whatever for assigning such mutually distinct species as webbi, valens 

 and woodhousei to drummondi as varieties, and it is still more prepos- 

 terous to consider them synonyms. The structure of the base of the 

 abdomen seems, among other features, to have been wholly overlooked 

 in distinguishing species of the webbi and valens type. In valens the 

 prothorax is undoubtedly very much shorter and more inflated at the 

 sides than in convexa, but the statement by LeConte that it is nearly 

 three times as wide as long is doubtless far overdrawn.^ In ocularis 

 the prothorax is more transverse than in convexa and is more ante- 

 riorly dilated, the eyes and antennas also being notably different from 

 those of convexa in prominence and color, but, as these points are not 

 mentioned by LeConte in regard to valens, further observation will 

 be necessary before deciding definitely the kinship of ocularis and 



^ This proportional width of the prothorax is very deceptive. I have 

 recently measured with dividers the width in terms of length, in cases where 

 the prothorax certainly seemed to be beyond doubt more than twice as wide 

 as long, as in Spinthoptera ocularis, for example, and the result proves that, 

 even in such cases, it comes far short of actually being even as much as twice 

 as wide as long. The comparative statements given in the descriptions of 

 the present paper, as well as all others of the writer, are not based upon 

 instrumental measurements, but are simply the ratios as they appear to his 

 eye. The deception is due, in most part at least, to the shape of the apex, 

 base and side margins, for if we had before us a geometric rectangle of the 

 actual extreme dimensions, there would be much less trouble in realizing the 

 true ratio. This goes to prove the necessity for stating the true dimensions 

 of all the parts of an animal in linear units, as advocated by the writer many 

 years ago, if we desire to record a description of the greatest possible value 

 foi' purposes of comparison. 



