APHILOTHEIS KADFCIS. 91 



also in the number, length, and depth of the furrows. 

 Some examples are quite smooth, and but for the 

 absence of the sharp pointed apex peculiar to the 

 galls of Andricus nudns, many small specimens might 

 pass as that species. Yet mature galls of A. guadrt- 

 Uiieatits often show a papilla Avlien dry; A. jmdus, 

 however, never attains the same dimensions. 



Considerable indecision appears to have existed 

 amongst writers as to the identity of this gall when it 

 was first noticed on the continent. Its great varia- 

 bility doubtless accounts for this, and it also affords an 

 explanation of its many synonyms, to which Schenck 

 unnecessarily contril)uted five. 



Some years it appears in great profusion, clusters 

 of eight and ten galls being frequently found on a cat- 

 kin stalk. A very fine example I found in 1907 con- 

 sisted of fifteen galls upon one stalk within a length of 

 23 mm. 



"Notwithstanding that this gall is very al)undant it 

 is l)y no means easy to rear the fly. From the 

 majority of the galls parasites are usuall}^ obtained ; 

 then the larva in a large numljer of instances does not 

 develop into the imago for two years " (' Alternating 

 Generations,' p. 91). 



Aphilothrix radicis, Fabiicius. 

 (Plates XXVI, XXX, div. A.) 



Cynips radicis, Fabr., Hartis^-, Sclieuck, Kalt., Marsliall : Aphilo- 

 thrix radicis, Mayr, Adler, Licbt., Fitch, Walker, Miiller ; Andricus 

 radicis, Mayr, Canierou. Mosley. 



English name of gall. — " The Truffle Grail." 



Position of gall. — On exposed roots, base of trunk and brandies 

 growing therefrom. 



Manner of growth. — Glabrous, sessile, solitary, conglomerated. 



Colours. -Cream, pink, orange, red, reddish-brown. 



Average dimensions of a mature specimen. — Height. 

 45 mm. -. length, 6<) mm. ; breadth, 40 mm. 



May be sought during any month of the year. 



Growth is complete l)v the end of the second autumn. 



The typical condition of the gall is plurilocular, but unilarval. 

 Usual number of ceils, aliout sixtv. 



