1979] 
Aiello — Phereoeca allutella 
135 
Discussion 
A number of Lepidoptera and Trichoptera make movable cases 
during larval life. In the Lepidoptera, movable cases are found in 
several families (e.g., Psychidae, Tineidae, Mimallonidae, Stenomi- 
dae), and vary among taxa, as to size, shape, and materials. They 
may be conical, oval, circular, spindle-shaped, dumbell-shaped, or 
irregular in outline, and round, flattened, or triangular in cross 
section. There may be an opening at one or both ends, and the case 
may have either a definite dorsal and ventral side or the sides may be 
interchangeable. Construction materials may include soil, frass, 
twigs, food particles, leaves, or organic debris, but always include 
silk. Among lepidopterous cases examined, the only ones resemblng 
those of Phereoeca belonged to several other species of Tineidae. Of 
these only Tinea pellionella (the case-making clothes moth) has been 
studied in detail (Reaumur 1737, Marlatt 1898). 
The case of Tinea pellionella is like that of Phereoeca in having 
two openings and no definite dorsal or ventral side; it differs in 
being less flattened, in being constructed of food particles (wool), 
and in the method of case enlargement used. The larva makes a slit 
along one side of the case from one end to about the middle. It adds 
a wedge of new material to the slit, and repeats the process on the 
other side at the far end. 
The cases of Trichoptera larvae also are made from silk plus 
materials collected from the habitat. Hanna (1960) described eight 
construction patterns used by Trichoptera larvae when making their 
initial cases. None of these in any way resembles the method 
employed by larvae of Phereoeca. 
I thank D. R. Davis (USNM) for determination of the moth, P. 
M. Marsh (USNM) for determination of the wasp, the Smithsonian 
Tropical Research Institute for use of facilities, and R. E. Silberg- 
lied (MCZ) for helpful criticism of the manuscript and the donation 
of countless squashed mosquitoes. Specimens of Phereoeca have 
been deposited in the National Museum of Natural History, Smith¬ 
sonian Institution, and the Museum of Comparative Zoology, Har¬ 
vard University labeled with the following reference numbers: Aiello 
lots 77-5, 77-75, 78-4, 78-5, 78-37, 78-53, 78-58, 78-73, and 78-99. 
