[Illustration: Fig. 1. _a_, Diamond-back Moth (_Plutella cruciferarum_); _b_, young caterpillar, dorsal view; _c_, full-grown caterpillar, dorsal view; _d_, side view; _e_, pupa, ventral view. Magnified 6 times. From _Journ. Dept. Agric. Ireland_, vol. I.]