544) CICADIDAE (p. 568). FULGORIDAE (p. 574). MEMBRACIDAE (p. 576). CERCOPIDAE (p. 577). JASSIDAE (p. 578). DIMERA (p. 544) PSYLLIDAE (p. 578). APHIDAE (p. 581). ALEURODIDAE (p. 591). MONOMERA (p. 544) COCCIDAE (p. 592). ANOPLURA (p. 599) PEDICULIDAE (p. 599). {1}CHAPTER I HYMENOPTERA PETIOLATA _CONTINUED_ SERIES 2. TUBULIFERA OR CHRYSIDIDAE—SERIES 3. ACULEATA—GENERAL— CLASSIFICATION—DIVISION I. ANTHOPHILA OR BEES The First Series—Parasitica—of the Sub-Order Hymenoptera Petiolata was discussed in the previous volume. We now pass to the Second Series. SERIES 2. HYMENOPTERA TUBULIFERA. _Trochanters undivided; the hind-body consisting of from three to five visible segments; the female with an ovipositor, usually retracted, transversely segmented, enveloping a fine, pointed style. The larvae usually live in the cells of other Hymenoptera._ The Tubulifera form but a small group in comparison with Parasitica and Aculeata, the other two Series of the Sub-Order. Though of parasitic habits, they do not appear to be closely allied to any of the families of Hymenoptera Parasitica, though M. du Buysson suggests that they have some affinity with Proctotrypidae; their morphology and classification have been, however, but little discussed, and have not been the subject of any profound investigation. At present it is only necessary to recognise one family, viz. Chrysididae or Ruby-wasps.[1] These Insects are usually of glowing, metallic colours, with a very hard, coarsely-sculptured integument. Their antennae are abruptly elbowed, the joints not being numerous, usually about thirteen, and frequently so {2}connected that it is not easy to count them. The abdomen is, in the great majority, of very peculiar construction, and allows the Insect to curl it completely under the anterior parts, so as to roll up into a little ball; the dorsal plates are very strongly arched, and seen from beneath form a free edge, while the ventral plates are of less hard consistence, and are connected with the dorsal plates at some distance from the free edge, so that the abdomen appears concave beneath. In the anomalous genus _Cleptes_ the abdomen is, however, similar in form to that of the Aculeate Hymenoptera, and has four or five visible segments, instead of the three or four that are all that can be seen in the normal Chrysididae. The larvae of the Ruby-flies have the same number of segments as other Hymenoptera Petiolata. The difference