74 THE ENTOMOLOGIST. 



solitary, it may be easily distinguished by always occurriug 

 on the bark of the Turkish oak (Quercus Cerris) in the form 

 of knobs, varying in size from a hempseed to a walnut. If a 

 specimen be detached from the twig it may be plainly seen to 

 have been growing on the woody part, seated on a very short 

 pedicle, and to have raised up the bark in its immediate vicinity. 

 It is found singly on the most slender young shoots, in the form 

 of a spherical knob, or occasionally it has so enclosed the 

 twig that its protruding sides meet exactly opposite the point 

 of its attachment. On the larger twigs we find a great number 

 of these galls so crowded together that each becomes flattened 

 at the point of contact, and the mass thus formed surrounds 

 the twig in the form of an irregular band, that sometimes 

 extends to three centimeters in length and thickness. The 

 longitudinal fissure in the bark, through which these galls 

 have forced their way, may be readily perceived if one of the 

 size of a hempseed or a pea has happened to remain unde- 

 veloped, and to grow separately on a thicker twig. The galls 

 appear at midsummer, and are of a light green colour, and 

 more or less clothed with a short tomentum ; later in the 

 autumn they assume a brownish yellow hue, and lose their 

 tomentum, more especially the larger ones, whilst the imma- 

 ture specimens often retain it. The interior of the gall 

 consists of a rather loose parenchyma : it is hollow in the 

 centre, and contains a moderately large, oval, inner gall, 

 which is seated at or near the base of the outer one ; some- 

 times this is quite detached, at others it is looselj^ adherent to 

 the substance. In the smaller specimens, which only contain 

 parasites, this inner cell is not developed, and we frequently 

 find, as in several other species of galls, little oval cavities, 

 arranged in a radiating manner in the parenchyma, and these 

 serve as homes for the parasites. This gall is not deciduous, 

 and specimens two or three years old, and partly destroyed, 

 may be often met with on twigs. The perfect insect emerges 

 in December of its first year. — G. L. Mayr. 



Cynips cerricola is accompanied by four inquilines, and 

 the distinctive characters of these, and of others of their tribe, 

 may be noticed on another occasion : — (1) Synergus variabilis 

 of Mayr — it appears from March to July in the second year; 

 fS) Synergus thaumacera of Dalman — April, second year; 

 (3) Sapholytus undulatus of Mayr — it appears in May and 



