74 THE ENTOMOLOGIST. 



by intermediate forms. Dr. Giraud has described three of 

 these varieties. The first variety, most frequently met with 

 (the true C. gkitiuosa), is subglobular, and is about a centi- 

 metre in diameter. Its base generally adheres so closely to 

 the twig or petiole that these produce impressions on the 

 gall. At the point opposite the base there is an umbilicated 

 cavity. On the whole, the basal half of the gall is more 

 swollen than the upper half. When fresh the gall is yellow 

 or partly red, and more or less glutinous ; when dry it is 

 generally brownish yellow, and loses its stickiness. In 

 section it exhibits a large cavity. The thin egg-shaped inner 

 gall is here either attached to the base or to the point 

 exactly opposite, but subsequently it sometimes appears 

 quite detached. The second variety (C. coronata) has, on the 

 whole, the fundamental form of the preceding. Its lower half 

 is, however, surmounted with a crown of recurved, shorter or 

 longer, projections. That part of the gall which lies above 

 the crown of thorns and bears the umbilic in its centre is 

 generally more swollen than in the galls of the first form, so 

 that the umbilic is far less conspicuous. This gall is gene- 

 rally of a lighter tinge, and far more glutinous and glossy. A 

 section exhibits a thicker layer of moderately hard gall- 

 substance and a smaller cavity, which sometimes occurs as a 

 circularpassage round the inner gall, thatadheres to the base by 

 means ofa very short, or somewhat longer, pedicle. It sometimes 

 happens, however, that the inner gall has only a basal attach- 

 ment, and still the cavity is present, although smaller than in 

 the first form. The third variety (C. miirata), in spite of its 

 different outward appearance, is the same species, but without 

 a cavity in the interior. The base has a flat extension, but 

 it generally adheres so tightly to the twig that the base 

 becomes strongly recurved. From this roundly swollen base, 

 which in mature galls is about a centimetre in diameter, 

 projects a cone or a thick style-shaped part, rounded at the 

 end and strongly umbilicated. The surface is smooth, of a 

 brownish red colour, and moderately glutinous. It shows no 

 cavity in the section, the inner gall everywhere closely 

 adhering to the gall parenchyma. A fourth form, which I 

 have twice met with, may be placed under the last variety, 

 C. mitrata. it differs, however, in having several excres- 

 cences at its base, in its upper part forming a plain with 



