282 BULLETIN 31, UNITED STATES NATIONAL MUSEUM. 



Numerous specimens of Chilosia have been determined, some of them 

 with certainty, by the facial i)rofi]e, antenme, coloration, neuratiori, 

 shape of abdomen, and structure of legs. Perhaps the most character- 

 istic is specimen Xo. 8781, which lies upon the side, giviufj an excellent 

 profile of the head. Other specimens seemed to approach Pijnza or 

 Psilota, though one could not say with absolute certainty that these 

 genera, in their modern acce])tatiou, actually occur anujug tliem, though 

 T very much think that one or both do. 



Rhingia seemed to be recognizable with sufticient certainty, tlie de- 

 termination based upon coloration, shape of abdomen, large wings and 

 almost typical neuratiou, and slender legs, especially well shown in 

 specimen ^o. 11099. 



It may safely be said that Syr])Jms, Chilosia, Chrysogaster, RJiinqla, 

 and Sphegina occur in the American Tertiary beds, to which may in all 

 probability be added Pipiza. There is yet another form which could not 

 be located in any of the known existing North American genera with 

 certainty. The specimen (No. 7035) is of large size, in shape much like 

 that of Mallota, the hind femora apparently much thickened, the an- 

 tennae rounded, the penultimate section of the fourth vein long, and 

 the anterior cross-vein basal and rectangular. The form is nearest 

 allied to MijioJepta. 



In conclusion, I cannot refrain from expressing my admiration of tlie 

 perfection and accuracy of the dipterological drawings, and the care 

 with which the specimens have been studied by Mr. Scudder. Mr. 

 Scudder has given a summary of our present knowledge of insect pale- 

 ontology in Professor Zittel's Handbuch der Paleontologie, from which 

 the following is given to complete the present status of our paleonto- 

 logical knowledge of this family: 



"A very obscure object from Solenhofen is referred by Weyenbergh 

 to CJtilnsia, and Giebel refers to a new genus, Remelia^ a minute Hy 

 figured by Brodie from the English Purbeck, but its reference here is 

 very doubtful. 



"In the Teitiaries this family is more abundant and varied than any 

 of the other families of Dlptcra cyclorrhapha. Burmeister and Terres 

 both recognize Microdon at Aix, Pipiza has been described from Rott, 

 Chilofiia from Wyoming, and seven sj^ecies of Syrphus from Oeningen, 

 Eadoboj, Bott, and Senegaglis, besides which it has been recognized in 

 amber; in amber, also, are found two peculiar genera allied to Ascia and 

 Xylota, besides Chilosia, Volucella, and Criorhina; Rhingia is noticed 

 at Aix, Eristalis descril)ed from Utah, Helopkilus and Merodon from the 

 Rhine, and Milesia from Wyoming. Lastly some thirty or more species 

 of various genera occur at Florissant, and a considerable number of 

 them in a remarkable preservation. 



"There are descriptions of Pipiza, Syrphus, Merodon, and Relophilus.^^ 



