l8 ' SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 5 1 



than those implied in close relationship, the following' is an excellent 

 case in point among the Coleoptera. Mr. W. Dwight Pierce makes 

 the statement that three species of Anthonomus (A. nigrinus, ccneo- 

 lus, and albopilosus) , which breed in the flower-buds of Solomon 

 spp. (S. carolincv.se, eleagini folium, rostratum, and torreyi) in 

 Texas, resemble each other so closely in the adult that they are often 

 confused by experienced coleopterists. Yet Air. Pierce, who has 

 studied the early stages of these species, has found that the anal 

 characters of the pupas serve to readily distinguish them. A. ceneo- 

 las and nigrinus belong in the same group, are distinguished in the 

 pupa by a slight difference in the proportions of the posterior termi- 

 nal structures of the anal segment, and in the adult only by color. 

 But A. albopilosus belongs in a distinct group, is inseparable in the 

 adult except by leg characters, and markedly different in anal 

 characters in the pupa. A. albopilosus is thus a case of con- 

 vergence toward ccneohis and nigrinus, which two are closely related 

 forms. It should also be mentioned that albopilosus has been found 

 recently breeding in great numbers in buds of Croton spp. Dr. 

 Chittenden is authority, however, for its former breeding in Sola- 

 tium spp. 



The reasons for such convergent evolution or parallelism are often 

 difficult to ascertain and are outside our subject. This case is intro- 

 duced from the Coleoptera merely as paralleling certain very similar 

 ones in the Muscoidea. For example, the species Achcetoncura 

 datanarum, A. promiscua, and Parcxorista futilis seem to form a 

 group similar to the above species of Anthonomus. The first two are 

 closely related, and the third furnishes a case of convergent evolu- 

 tion in their direction. All three forms are entirely cinereous polli- 

 nose, have the anal segment brassy, and the parafrontals and para- 

 facials golden pollinose. (Achcetoncura frenchi has a different 

 facies. but has been confused with the first two.) 



Similar groups will be found in the genera Tachina, Masicera, 

 Phorocera, etc. Another group is probably exemplified in Myio- 

 phasia spp., Phasioclista metallica, Bnnyomuia clistoides, and certain 

 other species. 



Such conditions as the above explain why specimens of tachinids 

 looking strongly alike and bred from the same 'caterpillar, perhaps 

 issuing on the same date, are at times found to belong to different 

 forms and ever to different genera. In such of these cases as are 

 due to convergent evolution and parallelism, the larvae and puparia 

 will be found to exhibit better differential characters than the adults. 

 No work connected with the taxonomv of the Muscoidea could more 



