MK. A. MtJLLER ON A CHINESE AUTICHOKE GALL. 429 



" TIio larger trees, producing acorns, are called Siang-li (the 

 generic name for the oali), wliilst those that are smaller and do 

 not produce acorns are called Tsing-hang. In its stem and 

 foliage the Ts'ing-hang is altogether similar to the Siang-li ; but 

 the colour of its leaves is a lighter green, and its flowers less 

 abundant " (p. 9) "" The Ts'ing-hantj tree grows on hills in- 

 terspersed with the Tsiang-li oak trees, being in fact of the same 

 kind, but devoid of flowers and fruit. A green ball is frequently 

 found developed at the extremiby of its twigs, consisting of hairs 

 as fine as the silky fibres of the Tsung tree (qu. a palm ?), but 

 somewhat tougher The plate annexed to the above descrip- 

 tion, a copy of which is here \vide p. 11] given, represents an oak 

 with leaves like those of a shallow-lobed form of Quercus robur, 

 and with three fruits (unless they are intended for the ' oak- 

 apple ' mentioned in the text), one distinctly stalked, the dense 

 squamee of the cupule entirely concealing the acorn, and looking 

 like those of Q. deniata, Thunb., though closely appresaed instead 

 of being more or less reflexed " (p. 10). 



" The oaks are never allowed to grow old here [Thong-kin-foo] ; 

 every eight or nine years they are cut down to the ground ; the 

 subterranean trunks throw up new shoots, which are again cut 

 down after the lapse of another eight or nine years, so that the 

 oak woods are merely copses" (p. 12). 



Britain and China lie far apart ; but, botanically speaking, the 

 genus Quercus is a good link between the two countries. It is 

 therefore worth while pointing out that with the aid afforded by 

 the life-history of a British Cynips the extracts given above bear 

 witness to the existence of a closely allied Chinese insect, AVIiat 

 my friend Mr.. Eiley, the State entomologist of Missouri, properly 

 styles " unity of liabit," jjoints out the way. Since it has come to 

 pass in Britain and on the continent adjoining that oaks are 

 felled wholesale, and are almost everywhere replaced by copsewoed, 

 wbicb has sprung up frcni their roots, an axillary excrescence called, 

 from its resemblance to an artichoke, the "Artichoke Gall " has 

 made its appearance in enormous numbers on the young oak- 

 shoots. It is the cradle of a cyuipideous fly named ApMlothrix 

 gemma;, Linn. {Gyni/ps fecundatrix, Hartig). The numbers of this 

 insect in Britain are now so great in some parts that they threaten 

 to render many bearing oak trees altogether sterile. The para- 

 sitic Hymenoptera appointed to keep this Cynips in check are now 

 altogether insuIEcient in numbers to cope with its rapid increase, 



