AttTflROCERtD SPECIES. 539 



ANTHROCERID SPECIES. 



In obtaining the materials for the study of the Anthrocerids from 

 every possible source, we have been repeatedly called upon to formu- 

 late an opinion as to what constitutes a species in this particular 

 genus. Few as are our British species, they afford representatives of some 

 of the chief sections into which this somewhat unwieldy genus naturally 

 falls, and in the study of their variation the question of species faces us 

 at every turn. Is A. nibicundus cospecific with A. purpuralis? Are 

 A. viciae and A. charon, Hb., the same species ? Is A. lonicerae distinct 

 from A. medicayinis ? Can A. dubia be a mixture of A. medicayinis 

 and A. ochsenheimeri ? Are A. trifulii and A. palustris distinct ? Can 

 A. seriziati, the most extreme form of A. palustris, be specifically 

 identical with A. syracmia, the most extreme form of A. trifulii' 

 Should A. hippocrepidis, St., be united with A. trifulii or A.filipenditlae ! 



The difficulty of species among the Anthrocerids does not lie so 

 much in the intergrades met with, as in the tendency for a given con- 

 dition of environment to produce a race with a well-defined facies, and 

 the consequent determination whether there is sufficient distinction 

 between two well-marked forms to warrant one in considering them 

 species thus we get the viciae-charon, the lonicerae-medicayinis, and 

 jilipendulae-hippocrejndis combinations. Not that intergrades do not 

 occur, trifolii and palustris appear to offer such, yet the question of 

 .ti/racnsia and seriziati as species turns rather upon their differentiation 

 from trifolii and palustris respectively, to which forms they are un- 

 doubtedly attached. Considering- these as combinations of the first 

 grade, i.e., the presumed species being little more than local races 

 with a well-defined facies, there are combinations much more far- 

 reaching in character, e.r/., not whether medicayinis = lonicerae or 

 oclisenlteiineri filipendulae, but whether medicayinis = ochsenheimeri 

 (the two having been combined as dubia, Staud.), and, therefore, 

 whether lonicerae fdipendulae, two very distinct insects in their 

 typical forms. The question of species, then, is a difficult one, and if 

 one sums up the characters presented by certain Anthrocerids, one 

 is often puzzled as to what should and what should not be considered 

 the limit of specific forms. 



Unfortunately in this genus, two out of the three early stages yield 

 no characters that can be considered of value in this direction. One 

 can often determine certain species of Lepidoptera by an examination of 

 the eggs or pupae alone. The eggs of Anthrocerids are, in their broad 

 characters, almost identical, and the pupae are equally generalised and 

 similar, even when the imagines are most diverse. They present the 

 same number of movable segments, the maxillae, antennae and 1st pair 

 of legs reach to almost exactly the same points on the 5th and 6th 

 abdominal segments, a slight difference in the colour or texture of 

 certain segments alone remaining. The larvae, too, are so little 

 specialised that their structural uniformity is only equalled by their 

 general similarity, a difference in ground colour, and the size of the 

 black markings before and after the warts (which extend in longitudinal 

 series throughout) being almost the only available characters at disposal. 

 The imagines, although maintaining what may be called an average of 

 stability, are subject to the most amazing variations, so that a single 

 normally 5 -spotted species, A. trifolii, may present the extreme 

 characters of A. lonicerae or A. erytkrus, and what is true of this, is true 



