I. THE COTTONY MAPLE SCALE. 



(Pulvinaria innumerabilis Katlivou. | 



Original home and present distribution. — This is a scale insect native 

 to the United States which was originally found by Dr. S. S. Eathvon 

 at Lancaster, Pa. Later it was found by Walsh and Riley and other 

 observers to be very abundant and occasionally very injurious in the 

 Mississippi Valley. It is frequently noticed in the Northeastern cities, 

 especially in Brooklyn, Philadelphia, Baltimore, and Washington. It 

 has been sent to this office by correspondents in Massachusetts, Ver- 

 mont, New York, Pennsylvania, New Jersey, Maryland, Virginia, North 

 Carolina, Georgia, Ohio, Indiana, Illinois, Michigan, Wisconsin, Iowa, 

 Kentucky. Tennessee, and Missouri, and what is apparently the same 

 species has been received from Fort Worth, Tex., Omaha, Nebr., and 

 from Idaho, Oregon, and Washington, as well as northern and southern 

 California. 



FlG. l.—Pulvinaria innumerabilis : a, newly-hatched young; b. female , third stage, from ahove; c, 

 same, from side; d, male, third stage; e, same, natural size, on leaf and petiole; /, same, enlarged, 

 on leaf petiole showing two specimens parasitized — all greatly enlarged except e (original). 



Food plants. — As its popular name indicates, this insect is generally 

 found upon maple. It seems especially to thrive upon the so-called 

 silver-leaf maple (Acer saccharinnm), but it is also found upon Norway 

 maple and the sugar maple, as well as upon Acer dasycarpum. It 

 occurs abundantly upon the box-elder {Negundo negundo), aud it or a 

 very closely allied species is found upon the Osage orange (Madura 

 aurantiaca). During the summer of 1898 it was found at Washington 

 by the writer occurring upon red mulberry (Morus rubra)] and it has 

 been received from Prof. George C. Butz, of State College, Pa., upon 

 Aralia japonica. According to Prof. C. V. Piper, the ^Northwestern, 

 form (occidentalis) affects apple, pear, alder, willow, hawthorn, poplar, 

 currant, and lilac, which diversity of food offers strong argument for 



