a96 



GALL-MAKING COGCIDS. 



These include some of our ''curiosities" in insect 

 life, for we have some of the largest galls in the 

 world. The gall is thought to be formed by the 

 stimulation to growth given by the feeding of the 

 gall insects on the tissues of the plant. At any 

 rate, the plant-tissues grow abnormally in this spot 

 and envelop the little coccid. Later, the soft plant 

 tissues may become Avoody and very thick, with 

 just a relatively small chamber for the insect in 

 the centre. (Plate 51, Fig. 4.) The female passes 

 practically the whole of her existence within the 

 gall; the latter is more or less rounded. There is 

 always an opening of small size at the apex, 

 through which impregnation of female takes place. 



The male passes the first part of his existence 

 in a usually much smaller gall (Plate 51, Fig. 2), and 

 it is, in most cases, very different in shape from 

 that of the female. It may be situated close to 

 or at a distance from the female gall. 



The genus Apiomorpha includes some of our 

 largest galls. Some are top-shaped, others 

 pear-shaped; while the large rectangular gall (Plate 

 51, Fig. 1), with curious flat tails, may be three 

 inches long. It is called Apiomorpha duplex. 



We cut open a green specimen (one of the pear- 

 shaped galls), and saw within the creamy, pear- 

 shaped wingless gall, with head down and body 

 prolonged to a point, (Plate 51, Figs. 4 and 5.) 

 We examined with a lens; the legs and sucking- 

 mouth parts could be seen. It secretes a powdery 

 material, which forms a soft lining to its home. 



