MICROSCOPIC OBJECTS. 67 



Fig. 133. Rostrum and Lancets of the Bug (Cimex lectu- 

 larius) , x 40. , 



This is another example of the beak for which the order 

 is noted; only, in this case, it is furnished with lancets. 

 These lancets are about -^ less than the lancets of the Flea (see 

 fig. 162). These insects seem to draw the blood, not by suc- 

 tion, as the Leech, but by moving the three thread-like setae 

 or lancets against each other ; this causes the blood to flow 

 up the rostrum or beak with a kind of capillary motion. The 

 eggs of this Bug make a good object where mounted opaque, 



To mount the insect it must be soaked in diluted potassa 

 fusa for at least twelve hours, then press out the contents of 

 the body, place it in the potassa for two hours more, well 

 wash in warm water, dry under strong pressure, soak in tur- 

 pentine, and mount in balsam. 



Fig. 134. Saws of Froghopper (Cercopis spurn aria), x 40. 



Of all our common British insects, perhaps this is one of 

 the least-known. Most persons have seen the frothy appear- 

 ance on branches and leaves in the early summer months, 

 and also know that it is commonly called Cuckoo-spit ; and 

 that is nearly all they know about it. Few persons have 

 examined this little insect with its various natural apparatus 

 for the several functions it has to perform, and without which 

 the species would soon be extinct. The mature insect is fur- 

 nished with extremely fine saws (see drawing), with which it 

 cuts a slit in generally the last annual shoot, and deposits an 

 egg. The larva, on leaving the egg, immediately covers itself 

 with a froth, in this way : fixing its beak (which organ is cha- 

 racteristic of the order) into the cellular tissue of the'plant on 

 which it is situated, it sucks up sufficient of the sap to cover 

 itself, and then pours out a secretion from the organs placed 

 at the end of its body ; this secretion is the froth. The insect 

 is thus protected, and passes through its stages, until it arrives 

 at the perfect state. The larva may be mounted in acetic 

 acid, or dried and in balsam. The mature insect is best 

 mounted in balsam. 



K2 



