770 CHARLES PauL ALEXANDER 
R. C. Shannon, on the Potomac River near the mouth of Dead Run, Fair- 
fax County, Virginia. They were found during the latter part of May, 1916. 
in a much-decayed maple log, where they were associated with the larvae 
of the syrphid fly, Temnostoma bombylans (Fabr.) (Barber, 1913). Greene 
attempted to rear the larvae procured at this time, but did not succeed. 
In May, 1917, he sent the writer one of the preserved larvae for study. 
Later Dr. Viereck was interested in the matter, and on May 27 he procured 
one fine, healthy larva, which was sent to the writer at Ithaca, New York. 
It arrived safely on the 29th, and was atonce placed in rearing. Unfortu- 
nately this larva died the day after it came into the writer’s possession, 
and this remarkable insect still remains unreared. Associated with this 
larva in the pieces of decaying maple in which it was shipped, were 
larvae of Temnostoma and a larva and a pupa of the tipulid Epzphragma 
solatrix. 
The evidences that this larva is that of Protoplasa are numerous. 
It belongs, without doubt, to the Nematocera, and the immature stages 
of all the remaining families of that division have been made known. 
Many features in this larva point strongly to the condition in other families 
of crane-flies. The eucephalous condition of the head, and the elongate 
breathing tube, are suggestive of the Ptychopteridae; the five-lobed 
spiracular disk, the anal tracheal gills, the metapneustic respiratory 
system, and other features, are very similar to conditions in certain 
Tipulidae. However, there are conditions obtaining here that are found 
nowhere else in the Diptera, so far as is known to the writer, such as the 
combination of a eucephalous head of primitive organization, a stout, 
-non-retractile breathing tube, the large, pinnately branched anal gills, 
the multisetose punctures on the head, and the details of structure of the 
mouth parts. The multisetose punctures are suggestive of the branched 
or plumose hairs of Ptychoptera, and give a possible hint of the origin 
and. ancestry of this condition in the latter group. The writer cannot 
but regard it as suggestive that the larvae are found in direct association 
with those of Epiphragma in saturated decaying wood. He has mentioned 
in other papers (Alexander, 1910:254, and 1919 d:883, 915) the remarkable 
superficial resemblance that exists between the adult flies of Hpiphragma 
fascipennis and those of Protoplasa, both forms having very hand- 
somely banded wings of a pattern not found in other species in the local 
fauna. 
