Mr. A. Murray's Monograph of the genu a Catops. 19 



coloured and more solidified form, such a circumstance will suf- 

 ficiently account for the differences to which I have been alluding, 

 whether in punctuation, depression, or colour. Indeed, such a 

 supposition accounts for mure; for it is not only in the thorax 

 that these differences exist, but also in the whole of the rest of 

 the body. C. castaneus, St., is darker and more deeply punc- 

 tate on the elytra also, and the deeper colour extends to the 

 autennse, which are slightly darker at the point ; and this is only 

 what might be expected : we always find that where a greater 

 infusion of colour has penetrated through an individual, it is not 

 confined to one part, but pervades the whole system. I also 

 look upon the acuminate sutural apex of the elytra (referred to 

 by Kraatz as being possibly a sexual distinction of C. angus- 

 tatus, P.) as another indication of immaturity. I have never 

 seen this in C. castaneus, St., but I have found it indifferently 

 both in the males and females of C. angustatus, F. As to 

 the differences in the form of the joints of the antennae of 

 C. angustatus, F., and castaneus, St., these are too slight, even 

 adopting absolutely M. Kraatz's own description, to allow us to 

 use them as characters for a species ; but I cannot entirely adopt 

 his descriptions without reservation, as, notwithstanding a very 

 careful examination of the specimens he sent me, I have scarcely 

 been able to detect the differences he alludes to. Turning back 

 to his description, it will be seen that the only differences given 

 are the following : — In C. angustatus, F., he says, the third joint 

 is nearly twice as long as either the second or fourth. In 

 C. castaneus, he says, the third is distinctly longer than either the 

 second or fourth. In angustatus the seventh and ninth are said 

 to be equal in length. In castaneus the ninth is somewhat 

 shorter than the seventh. In angustatus the last joint is said to 

 be " longer than the preceding, long cylindric and acuminate.^' 

 In castaneus it is " almost twice as long as the preceding, sharply 

 acuminate." The differences here given are thus exceedingly 

 minute, so much so as to be inappreciable by an ordinary ob- 

 server. Now I know that in undisputed species in this genus 

 considerable differences are to be perceived in different indivi- 

 duals in the relative thickness, &c. of the joints of the antennae ; 

 80 much so as to make the antennae appear decidedly more 

 clubbed in the one than the other. This minute measuring of 

 the joints appears to me therefore an unsafe character, not to be 

 adopted. There only remains the difference in the form of the 

 posterior trochanters in C. angustatus, F., and castaneus, St. On 

 this I shall only observe, that M. Kraatz admits that there is 

 great variation in the development of these parts, but seems to 

 think there is an impossibility in a transition taking place 

 between a trochanter having a projecting curved tooth at the 



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