762 



CLASS IV. INSECTA. 



larvae eating up the larvae of the rightful owners, and sometimes, apparent- 

 ly, caterpillars stored up by the rightful owners as food for their larvae. 

 The family is widely spread and has some hundreds of species, about 

 twenty of which are British. They are brilliantly coloured and fly swiftly 

 in hob, sunny places. Chrysis (Fig. 492), Parnopes, Cleptes. 



Series 3. ACVLEATA. 



Trochanter as a rule not divided ; females (both perfect females and workers) 

 with a sting, except in some ants ; antennae of females with twelve segments, 

 of males with thirteen. 



This series is mainly characterized by a change of function and structure 

 in the ovipositor. This ceases to transmit the ova these pass to the 

 exterior at its base and becomes a weapon of offence, the sting. The 

 larvae are white grubs with no legs, and they live in cells provided for 

 them by the imagines ; until a late stage they are aproctous. The 

 pupa is soft. The sting (Fig. 485) consists of a sheath, a director paired 

 in its origin, and a pair of spicules or needles. The last segment but 

 one of the abdomen bears in the late larva four papillae : of these the 

 two inner form the director and the two outer the sheath. The seg- 

 ment next in front, the eighth abdominal, bears but one pair of papillae, 

 and these form the spicules. The question of the homologies of these 

 organs with abdominal limbs is a matter of dispute.* In the imago 

 of the male sex the two last segments are tucked into the preceding 

 segments ; in the female three segments are thus hidden. 



Fam. 16. Apidae (Anthophila). Some of the hairs clothing the body 

 are feathered or plumose : the mouth parts are usually elongate ; the 

 proximal segment of the posterior foot is enlarged. The Apidae are often 



FIG. 493. Apis mellifica. a queen ; 6 worker ; c drone. 



social, with a grade of infertile females known as workers. This family is 

 of considerable size with some hundred and fifty genera and ten times as 

 many species. In many cases the posterior legs, especially of the workers 

 (Fig. 494), are highly modified to carry home the pollen which is kneaded 

 into " bee-bread." The pollen may be simply entangled in the hairs or 

 damped and moulded into pollen-plates. The proboscis may be short ; 

 but in the Hive-bee, Humble-bee and others the maxillae (both pairs) 

 are drawn out, and in repose the proboscis lies with its distal parts doubled 

 back along the ventral surface of the body. The ligula is said to be 

 protruded by fluid forced into it from the general body-cavity. Bees 

 absorb the nectar from flowers and store it in their crops until the time 

 comes for them to regurgitate it as honey. During its stay in the crop 



* v. Heymons, Morph. Jahrf-., xxiv, 1896, p. 178. 



