36 Psyche [April 



in their form and orientation characters constituting an aggrega- 

 tion of new qualities. 



In presenting these descriptions, it is with the hope that these 

 forms may again he collected and . the adult stages of the cecido - 

 zoons be obtained. 



Not until the descriptions of the adults appear should names 

 be attached to galls; in the present paper the forms have been 

 given a number which can readily be referred to by any future 

 investigator. I should like to here repeat a statement made in 

 an earlier paper : "The custom on the part of some, of applying a 

 specific name to an insect or mite, merely on the basis of the 

 intimately associated gall, is to be deplored." 



The familiar "catch-all" generic names have been used in those 

 cases in which the nature of the parasitic organism was determined, 

 viz., "Cecidomyia" for an itonidid form, "Cynips" for a cynipi- 

 dous form, and "Eriophyes" for a mite gall-maker. 



The galls herein described and believed to be heretofore un- 

 reported, are arranged on the basis of the plant affected. The 

 plant genera are arranged alphabetically, Gray's ]\Ianual being fol- 

 lowed in the matter of nomenclature. 



• Amelanchier 

 Cecidomyia sp. Cecidium nov. Fig. 1. 



1. On Amelanchier canadensis (L) Mefic, leaf; prosoplasma, 

 appendicular, diverticulum type; stout balloon-shape with atten- 

 •uate tip, 3-5 mm. long, 2-3 mm. wide, reddish purple, surface, how- 

 ever, with bloom which gives it a l)luish tinge; galls commonly 

 found in gi'oups of two, on under side of leaf, each gall tilted out 

 of the perpendicular position; opening in leaf-blade on side oppo- 

 site the gall, minute, slit-like with definitely raised lips; cavity 

 small in the broader, distal part connected with opening by a rela- 

 tively narrow canal, walls thick with rather prominent veins; not 

 common. Cedar Point, 0. Types in author's collection. 



Cecidomyia sp. Cecidium nov. Fig. 2. 



2. On intervenal areas of leaf of Amelanchier canadensis (L) 

 Medic, (service berry) ; prosoplasma, sub-ovid, laterally flattened, 

 the sides paralleling the secondary veins, extending from both sides 

 of the leaf, long axis pei'pendicular to the blade, 2-3 mm. long, 



