BIOKHIZA RENUiJ. 101 



by W. H. Hammond, of a transverse section through 

 a bud with ova in situ, and of three ova alone, deserve 

 careful examination. 



Biorhiza renum, Hartig. 

 (Plate XXXIV.) 



Trigonaspis remim, Mayr ; Trigonaspis megaptera, Cameron; 

 Biorhiza renum, Griraiid, Adler, Miiller, Majr, Fitch. 



English name of gall. — "Tlie Kidney Gall." 



Position of gall. — On the under- surface of leaf. 



Manner of growth. — Glabrous, glossy, gregarious, con- 

 glomerated. 



Colours. — Yellowish-green, green, red, purple, dark brown. 



Average dimensions of a mature specimen. — Eeniform 

 type : Height, 1 mm. ; length, 2 mm. ; Ijreadtli, 1 mm. 



May be sought during the months of September and October ; 

 occasionally November. 



Growth is complete liy the end of October. 



The typical condition of the gall is unilocular and unilarval. 



The larva pupates in the gall. The imago emerges during 

 May and June. 



Parasites, Nos. 2, 10, 59, 74, 105. Inquilines, Nos. 134, 138, 

 139, 140, 143, 145. 



Alternate sexual generation : Trigonaspis crustalis, Hartig. 



The ovoid and spherical forms, and solitary speci- 

 mens of this gall are apt to be confused with those of 

 Neuroferus osfreus by anybody beginning to collect oak 

 galls. Many examj^les are very much alike. Several 

 features, however, serve to distinguish the species. B. 

 remim is rarely spotted, and then not to the same 

 extent as JSf. ostreus, the latter though is sometimes 

 without spots. B. renum never has the little valve- 

 like membraneous pieces of leaf tissue at its base, nor 

 the minute papilla3 on its surface as does N. osfreu.s, 

 while the latter never occurs in j^arallel rows. 



The shape and mode of growth of this gall are both 

 distinctive and attractive. The shape is that indicated 

 hj its specific appellation, viz. like a kidney. Occa- 

 sionally specimens develop into an ovoid and a spherical 



