mS CEE. 
ON CERTAIN PIERIS CATERPILLARS. 
BY WM. T. M. FORBES, WORCESTER, MASS. 
Last spring while Instructor of Biology at Robert College, Constantinople, 
Turkey, the opportunity came to me to breed the caterpillars of Pieris daplidice, 
rapae and brassicae, side by side, and make comparison of them in all stages. Dur- 
ing this time however I was away for more than a week, and was considerably in- 
terrupted by my regular work, with the result that there are several gaps in the 
descriptions. 
I have come across no descriptions of P. rapae or brassicae, which take note of 
the tubercle arrangement. ‘There is a quite full description of all the stages of dapli- 
dice in “‘ The Entomologist” XXXIX, 193 (1906) by F. W. Frohawk, but this con- 
tains a few details not emphasized there, which may be useful in comparison with 
the other two. Judging by this description P. daplidice will have in stage IT the 
tubercle arrangement of brassicae, rather than of rapae. It differs already of course 
rather widely in marking, showing the yellow subdorsal band. 
The three species studied are of special interest as representing the three sub- 
genera of Pieris. All three groups are represented in the Eastern States. Pieris 
(rapae) by rapae and the very rare oleracea; Pontia (daplidice) by protodice; and 
Mancipium (brassicae) by monuste, in the Southeast. 
Two other species were captured in Constantinople, but males only; Pontia 
chloridice and Pieris (typical) nape. 
I am especially indebted to Mr. J..W. H. Harrison for suggestions, and for the 
method of getting eggs. 
An assortment of Cruciferous plants, most of them in flower, were placed in a 
bottle of water, with the space around their stems filled up with paper. Then a 
large bell jar was inverted over the whole, without any ventilation, the females were 
introduced and the whole set in the sun. ‘The air inside became very damp, so much 
so that one female got stuck to the glass by her wings and had to be released. But 
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