350 PHYSIOLOGY. 



upon seeds. To these the larvae of the Curculios especially 

 have recourse. The Apion Jrumentarum and black Calandra 

 granaria have acquired a fearful celebrity from this circum- 

 stance; the nut weevil also, Balaninus nucum, which bores 

 the kernel of the hazel, and the cherry weevil, Anthonomus 

 druparum, which devours the kernel of the sour cherry 

 (Prunus cerasus}, and which are frequently found fully 

 developed in cherry-stones, are well enough known. 

 II. Fluid aliments which are taken up by suction or lapping. 



These are, 



1. From the animal kingdom, and consist of, 

 a. Fresh animal juices. 



These substances support the majority of toothless parasites 

 which are distributed upon all the warm-blooded animals. 

 They consist of all true lice and bed bugs, which imbibe only 

 blood. Some are parasites only during certain portions of 

 their lives, for example, the flea and the Diptera pupipara 

 in their last stage ; others, as (Estrns and the Ichneumons, 

 only as larvae. The remarkable Rhiphidoptera also are para- 

 sites chiefly as larvae, for, inserted between the abdominal 

 segments of many wasps and bees, they project into the 

 abdominal cavities of these insects, but push their heads 

 outwardly. It is still uncertain how they feed. The perfect 

 winged insect appears not to be a parasite. The Ichneumons 

 have a similar mode of life, for they live as larvae in the larvae 

 of other insects, and are fed by their fat ; but subsequently, 

 when they are full grown, they attack the nobler organs, and 

 thereby kill them. The perfect winged insect sucks the 

 juices of flowers. Other genera, which are parasitic as larvae 

 upon insects and cold-blooded animals, are, in the Coleoptera, 

 Drilus, which is parasitic upon snails, and Symbius, Sund., 

 whose larva feeds upon cockroaches. The parasitic state of 

 the larva of Melo'e is still more remarkable, it lives upon 

 bees only until its first moult, and in this state has been 

 formed into the apterous genus Triungulinus, by Desmoulin ; 

 it is probable that it subsequently goes into the earth, and 

 lives upon the roots of plants. There is a beauty in the 

 almost constant law which makes the parasites of warm- 

 blooded animals so during their whole lives, and they there- 



