C. W. Johnson.
Noes on the Variation in the Venation of the Species of the Genus Leptogaster.
Psyche 20:162-163, 1913.

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162 Psyche [October
'The cocoons were on trees, exposed to the natural weather con- ditions of St. Louis during the winter.
3. Telea polyphemus Cramer.
Four larvae of this species taken in the woods spun their cocoons within three or four days after being caged, and emerged as follows : Sex. Pupated. Emerged. Duration.
d" 9/19/'10 5/12/'ll 235 Days.
Q 9/%/'10 5/13/'ll 233 "
d' 9/23/'10 5/16/'ll 235 "
d" 9/27/'10 5/ll/'ll 226 "
At first glance the figures above seem to show that the insects emerged in the order in which they pupated, but in the fourth instance we see that the individual which was the last to pupate emerged as an adult before any of the others. It would be of interest to record similar data from year to year .from one or more localities, in an attempt to discover the causes underlying any variation in the duration of the pupal period, and to discover if the pupal duration is in any way correlated with the longevity of the imago. We have found in connection with other work that the pupal period of the Cecropia moth varied greatly under changed conditions of temperature and moisture. ST. Louis, Feb. 21, 1913.
NOTES ON VARIATION IN THE VENATION OF THE SPECIES OF THE GENUS LEPTOGASTER.
BY CHARLES W. JOHNSON.
Boston Society of Natural History, ~oston, Mass. In The Entomologist for July, 1913, vol. 46, p. 213, under the title "A Fossil Asilid Fly from Colorado," Prof. T. D. A. Cockerel1 proposes Tipuloguster "a new subgenus (or genus?) " for the recent Leptogaster budius Loew, based on the following characters: "The anal cell is narrowed apically as in L. hellii but the second pos- terior cell is no more produced basally than in Cophura, This also has the second submarginal cell shorter than in the typical Leptogaster. while the distance between its base and the anterior



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19131 Johnson-Notes on Variation in Venation of Genus Leptogaster 163 cross-vein is much greater." To one having a large series of L. bad& or a large number of the species of Leptogaster, the attempt to make a genus or even a subgenus on such trivial characters shows that the author had very little material at his command and had no idea how variable these characters are even in the same species.
Anal cell.
The fifteen specimens of L. badius before me show the following variations: twelve females have the anal cell narrowed but varying from one in which the cell is very narrow and almost closed on one wing, to others in which the outer portions of the veins are almost parallel; in two males they are parallel, as in the typical Leptogaster.
In L. testaceus, a closely related species, three have the venation as in L. badius and two have the anal cell closed. In L. incisularis Loew, the anal cell is only slightly narrowed at the margin. L. annulatus Say, marinus and flavipes Loew, virgatus Coq., clavipes and obscuripennis Johns., and atrodorsalis Back., all have the anal cell as in the type of the genus L. cylindrica DeG. (L. tipu- loides Fabr.). On the other hand, in L. brevicornis and pictipes Loew, and floridensis Johns., the sixth longitudinal and the anal veins are widely divergent and consequently the anal cell is widest at the margin of the wing.
Second posterior and second submarginal cells. Here again we find all gradations between the type species and L. badius. L. annulatus and atrodorsalis which have typical anal cells, have the second posterior cells "less produced basally" than in L. badius; the former however, has a long second submarginal cell and the latter a short one. In L. murinus, clavipes, obscuripennis and virgatus, the base of the second posterior cell is produced almost as much as in L. cylindrica but the second submarginal cell is as short as in L. badius. In the species with broad anal cells, L. pictipes and $or- idensis have the second posterior cell scarcely produced basally, the former has, however, a short and the latter a long second sub- marginal cell, while in L. brevicornis the second posterior cell is strongly produced basally and the second submarginal cell is long. The variation in the length of the second posterior cell was pointed out by Dr. E. A. Back (Trans. Amer. Ent. Soc., XXXV, 157, 1909). In referring to what he terms the anterior intercalary



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