11 



tity of E. pyramidata and E. marmorea. Westring, who had a g 

 specimen of E. pyramidata at his disposal, and subjected it to an 

 accurate comparison with cf of E. marmorea, considers himself to 

 have found in the colour and form of certain portions of the male's 

 butfms genitalis differences, that he looks upon as specific and con- 

 stant, and he therefore preserves E. pyramidata as a separate species. 



I have however myself subsequently obtained two male speci- 

 mens of E. pyramidata (from Germany) preserved in, spirits, and 

 have now endeavoured to test as strictly as possible the tenableness 

 of Westring's alleged characteristics. In neither of these specimens have 

 I been able to recognize any of the peculiarities, which Westring 

 observed in his example of E. pyramidata <f , but they agree exactly 

 in the points adduced by him, as well as in every thing else, the 

 colour of the abdomen alone excepted, with the accurate description 

 he has given of E. marmorea ci*. 1 can explain this only by sup- 

 posing, that Westring's specimen, which had first been preserved 

 in spirits and afterwards mounted on a pin, had in these processes 

 been somewhat changed in form and colour. Moreover the differences, 

 which Westring says he has observed, are very trifling, and he 

 himself seems to suspect, that they might perhaps not be found in 

 fresh and uninjured specimens of the animal. Even the "tooth" on 

 a "gibbus", which Westring last of all mentions as found in E. 

 marmorea, but not in E. pyramidata, is in my specimens as distinct 

 in the latter as in the former. 



Menge, like Westring, makes E. marmorea and E. pyramidata 

 separate species, and does not even mention that their difference has 

 ever been questioned. I have endeavoured conscientiously to test 

 the tenability of the differences alleged by him as existing between 

 them, and have found, that these differences, as far as 1 have been 

 able to verify them at all, are not constant. I have not been able 

 to find any constant difference in the colour either of the cephalo- 

 thorax or legs , neither can I see that the cephalothorax in E. pyra- 

 midata is broader in front than in E. marmorea. That I can dis- 

 cover no difference in the organs of copulation, has been already 

 stated; and when we carefully compare Menge's descriptions of these 

 organs and the figures he has given of them, letting figures and 

 descriptions mutually complete each other, it appears still impos- 

 sible to discover wherein the difference lies. The dissimilitude dis- 

 played in the elates of the legs and palpi, according to Menge, are 

 greater; but with them the case stands thus. The palpal elate of 



