1915 ] 
Muttkowski and Whedon: Gomphus Cornutus 
99 
If they were dragon flies, and they were taken at the surface and 
not beneath it, the birds may have accounted for the total ab- 
sence of adults of Gomphus cornutus where so many had trans- 
formed. 
After being photographed in the field both the male and female 
of Gomphus cornutus were removed to a cage in a laboratory win- 
dow where they matured their colors quite fully. The accom- 
panying photograph of the male (fig. 4) was taken after this 
captivity of several days. 
In size, depth, vegetation and surrounding topography this 
pond was very similar to the one at which Gomphus whedoni 
was taken at Iowa City, Iowa, on June 9th, 1908. 
Small ponds seem to be the habitat characteristic for the 
nymphs of the Arigomphus group. Muttkowski has taken G. 
cornutus at Milwaukee near a pond similar to that described. 
Walker collected and bred nymphs of G. furcifer from a similar 
pond. Needham and Hart have described like habitat prefer- 
ences for the nymphs of G. australis , villosipes, and pallidus. The 
habitat of G. lentulus is unknown. But for the remaining Ari- 
gomphus species suhmedianus and subapicalis Williamson (1914) 
cites “pools along the railroad” and “an artificial lake along the 
R.R.” as being frequented by the adults. 
As a group, therefore, the species of the Arigomphus group 
evince an uncommon unity in their habitat preference of still 
waters, such as ponds, puddles, artificial lakes, sloughs, etc. 
[Anent Gomphus lentulus Needham.] 
In a footnote to his 1914 paper Williamson mentions the unfortunate 
loss of the type of G. lentulus Needham. Williamson states, “This loss 
is the more unfortunate from the fact that lentulus, like australis, was not 
figured, nor were characters for separating them from their closest allies 
pointed out.” In addition Williamson refers to figures and some de- 
scriptive notes by the writer published in 1911. 
It is well to note here that I had no doubt of the correctness of this 
determination at the time it was made. My descriptive notes were in- 
tended to supplement Needham’s description while the figures supplied 
an obvious taxonomic need. As to the identity of the Brooklyn Museum 
specimen, even at this late date I recall perfectly the close agreement 
between the specimen and Needham’s description. This is especially 
true of the appendages. 
“Superior appendages shorter than the inferiors, strongly divergent, 
straight, scarcely tapering, suddenly obliquely truncate on end, with an 
