146 THE CAUSES WHICH PROPAGATE 



Landois enumerated as many as 238. They appear first to have 

 been detected by Westring in Sweden. 



Any one who cares to try the experiment, can easily test the 

 musical capacity of a dead Longhorn by nodding the prothorax 

 on the mesothorax ; and for this purpose even dry and subse- 

 quently relaxed species are serviceable. That the respiration is 

 intimately connected with the music, if it does not add to its 

 intensity, I infer from the manner of the jDoricardions, which 

 only creak when the sunshine falls on them ; and if the position 

 of the large spiracles (2a spr.), lying beneath the prothorax, be 

 remarked, it will be comprehended how, every time the prothorax 

 nods up and do^vn, these are exposed and recovered. 



But the stridulation of these elegant beetles may also be 

 studied in our walks in this country, northern and isolated 

 though it be, as many musical kinds'^ are distributed through 

 the wooded districts of England and Scotland, within their proper 

 climatic and floral limits. The Longhorns in which a suscepti- 

 bility for instrumental music is most often noticed are the Musk 

 Beetles, found on the trunk of willows, and the yellow species of 

 ClytuH, occurring plentifully in England on the old posts in which 

 they propagate. The musical organ of one of these is that shown 

 on Plate V., Fig. 2a. Then, again, there is the Timber Man Beetle 

 (Plate v.. Fig. 2b), more abundant in Scotland, where it maybe 

 met with flying in the fragrant glades of the Braemar pine- 

 forests, with its long antennae streaming to the wind ; or some- 

 times seated on felled logs of the sole indigenous fir, with these 

 feelers timidly spread out like compasses, a habit which is said 

 to have acquired it its Scandinavian nickname. Many more 

 kinds are highly musical, such as the Poplar Beetle, and others 

 of the genus Saperda, Fab. — a genus that includes species whose 

 grubs, like those of certain weevils, occasionally form vegetable 

 gall ; and Mr. C. O. Waterhouse, who has had opportunities of 

 listening to the creaking of the large black Lamia iextor, Fab., 

 a grim hermit of old and decayed willows, informed me it 

 possesses by far the most powerful and effective instrument of 

 our native Longhorns. 



Besides the goat-like Ceramhycidce, many a slim, gaily- 



* Cerambyx, L., Aromia, Serv., Astynonius, De Jean, Lamia, Mesosa, Meg'., 

 Saperda, Fab., ('Iijtiis, i\ib. 



