The Saw-flies (Tenthredinoidea) collected by the Canadian 
Arctic Expedition, 1913-18. 
Alex. D. MacGillivray^ 
The specimens of Tenthredinoidea collected by this Expedition were secured 
with one exception, by the entomologist of the expedition, Mr. F. Johansen. 
When the material obtained is compared with that described by Kincaid, the 
entomologist of the Harriman Alaska Expedition, a striking difference is noted. 
There was secured from southern Alaska by the Harriman Expedition repre- 
sentatives of eight groups, families and subfamilies. The collection of the 
Canadian Arctic Expedition contains representatives of three groups, two of 
which are represented by single species and specimens, which were collected at 
Nome, Alaska. One of these belongs to a group not represented in the collection 
of the Harriman Expedition, the Siricidge. All of the specimens from the 
northern part of the Northwest Territories belong to the subfamily Nematinse 
of the family Tenthredinidse. This restriction is further striking in that all the 
species belong to those genera with cleft claws. The larvse of the species of 
certain of the genera feed only upon willow, while in others the majority of the 
species feed upon willow. 
Some of the new species^ described on the following pages may prove to be the 
same as some of the species described from the European fauna. There is less 
liability for confusion and danger from recording species from our fauna that do 
not belong to it by giving names to these species, and this method has been 
followed. If later studies prove any of the species to be identical with species 
described from Siberia or Europe, it will be a simple matter to record them as 
synonyms. The length given in the case of the larvse is for individuals supposed 
to be mature. The statements enclosed by quotation marks are from the original 
notes prepared by Mr. Johansen, to whom I am indebted for reading the original 
manuscript of this paper, and for many corrections and suggestions. 
The following suggestion of Mr. Johansen will be of great value to future 
investigators and travellers collecting and breeding saw-flies in the Arctic 
regions; "From my notes it is evident that no saw-fly imagines are found in the 
Arctic outside of the months of July and August (9-10 weeks), a fact that I 
think is worth mentioning in the report, so that one understands that the speci- 
mens collected outside this period are all larvse or pupse." 
Uroeerus flavicomis Fab. 
A single female collected at Nome, Alaska, specimen No. 83F. This 
specimen differs /rom the description of Bradley in that it has the first and sixth 
and part of the seventh segment of the abdomen and the cornus yellow or 
brownish instead of the second, seventh, eighth, and sometimes the first more or 
less. 
"A big woodwasp {Teredo) caught this summer 1916, in the town of Nome, 
Alaska, was given to me here. It probably had been imported (as larva or 
pupa) from the states with lumber, and then emerged in Nome later" Bradley 
reports this species from Alaska and Siberia. 
^Contributions from the Entomological Laboratories of the University of lUinois, No. 56. 
^The types of all new species described in this report are deposited in the National Collection 
of Insects, Ottawa. 
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