CHRYSANTHEMUM MIDGE. 



Galls : They occur, three or four in number, at the extremity of the upper and lower 

 surfaces of the stem of the Chrysanthemum atratum Jacq., which is irregularly rounded, 

 varying in size from a large hemp seed to a large pea. Outside naked, consisting of a 

 fleshy homogeneous mass in which occur small, elongated cells or chambers each being 

 inhabited by a larva. 



Distribution: On Raxalpa about 5,000 feet above sea -evel. (E. Berroyer.) 



From this date, until it was first reported by Felt in the United 

 States, frequent references are found in literature relating to its occur- 

 rence and synonymy. Among these may be listed the following: 

 Kiibsaamen (4, p. 375), Kieffer (5, p. 21), (6), (7, p. 351, 353), (13), 

 Baldrati (8, p. 40-41), Kertesz (9, p. 69), Houard (11), and Kuster 

 (12, p. 77, 274). 



On March 26, 1915, R. H. Pettit of the Michigan Agricultural Col- 

 lege had his attention called to the existence of an infestation occur- 

 ring in large chrysanthemum houses at Adrian, Mich. Specimens were 

 submitted to E. P. 

 Felt (14), State ento- 

 mologist of New York, 

 who in April of that 

 year determined it as 

 the chrysanthemum 

 midge, Diarthronom- 

 yia Jiypogaea (F. Low) . 

 In 1916 A. Gibson (21) 

 reported the occur- 

 rence of the midge at 

 Ottawa, Canada. 

 Subsequently, reports 

 of its occurrence have 

 been received from widely separated points, both in the United States 

 and Canada. According to California florists, this pest has been 

 present in that State for about 15 years. 



DISTRIBUTION IN THE UNITED STATES AND CANADA. 



To date, the midge has been reported from California, Connecticut, 

 Delaware, the District of Columbia, Georgia, Illinois, Indiana, Maine, 

 Maryland, Massachusetts, Michigan, Minnesota, New Hampshire, 

 New Jersey, New York, Ohio, Oregon, Pennsylvania, Rhode Island, 

 South Dakota, Tennessee, and Virginia, as well as from Ottawa and 

 Victoria, in Canada. 



Since the first records of its occurrence and seriousness were report- 

 ed from the Middle West it would appear that the distribution of 

 infested plants from this region was the source of its further spread 

 to the other sections of the United States and Canada. 



Its distribution, as indicated on the accompanying map (fig.l), is 

 almost wholly confined to the larger chrysanthemum-growing regions 

 of the United States, which include the areas surrounding the Great 



Fig. 1. — Map showing distribution of the chrysanthemum midge 

 in the United States and Canada. 



