REPORT OF THE STATE ENTOMOLOGIST IQG/ II9 



The forms of the first (and second) type, consisting of fuzzy, 

 velvety or frostHke patches of slender, tangled, or capitate hairs 

 (trichomes) were formerly described as fungi and will be found 

 listed in botanical papers such as that of de Schweinitz 1834 in the 

 Transactions of the American Philosophical Society, volume 4, page 

 289 [see also Professor Peck 1869 in 22(1 Annual Report of the New 

 York State Museum, and Persoon's Mycologia Europaea, 1822. 

 p. 2]. The subgenus Phyllerium was employed by these writers 

 for forms with simple trichomes, while Erineum proper or Grumaria 

 signified those with capitate or mushroom-shaped trichomes, as 

 on right hand side of the figure, type i. Cecidium is a general term 

 for a galhde formation whether acarian or otherwise. 



Forms occurring in New York State are indicated by an asterisk 

 ("") preceding the number in the following catalogue. 



The writer's thanks should be here expressed to those who have 

 given generous assistance and encouragexicnt in ^'-'^ preparation of 

 this paper, as well as cjf others yet to be published. He is under 

 special obligations to Prof. Nathan Banks of the National Museum, 

 Prof. P. J. Parrott of the Geneva Experiment Station, Dr E. P. 

 Felt, State Entomologist, Prof. C. H. Peck, State Botanist, Mr 

 D. B. Young, Mr J. R. Gillett, and Mr Stewart H. Burnham, be^ 

 sides others who have aided with specimens or information. 



Acer glabrum (dwarf maple) 



1 A purple erineum in large patches at tips of the lobes and on 

 upper side of the loaf; sometimes sprinkled over under side. 

 Trichomes (hairs) with long stalks. 



Garman '92,^ no. 5 Col. 



There are specimens in the State Herbarium, without locality, 

 agreeing with this but bright crimson in color ; they are probably 

 from Utah. 



Acer negundo (box elder) 



2 A white erineum or shallow dimple on under side of leaf, some- 

 times involving entire leaves of young or basal shoots. 



Garman '83, p. 136 (Phytoptus sp.) 111. 



3 Irregular wartlike swellings on upper surface of leaf, green 

 to gray, lined below with a green to rusty-brown " granular secre- 

 tion." 



Jarvis '07, p. 59, fifth sp. Ont. 



This may be identical with the preceding. 

 ^ See Bibliography at the end. 



