354 MAINE AGRICULTURAL EXPERIMENT STATION. I916. 



really should be counted as but one single character. Finally 

 with respect to two character groups there is no difference 

 between the treated and the untreated. 



We may evaluate our results in general terms as follows : 



1. There is no evidence that specific germinal changes have 

 been induced by the treatment, at least in those germ cells 

 which produced zygotes. 



2. There is no evidence that the germ cells which produced 

 zygotes have in any respect been injured or deleteriously 

 affected. 



THE SEPARATE INHERITANCE OF PLUMAGE 

 PATTERN AND PIGMENTATION IN PLYMOUTH 

 ROCKS.* 



This paper gives the proof, based on Mendelian breeding 

 experiments, that in the Barred Plymouth Rock the barred 

 pattern is inherited as a separate unit character, distinct from 

 the pigment which makes the pattern visible, which constitutes 

 another unit character. It is shown that the White Plymouth 

 Rock inherits the same pattern as the Barred Plymouth Rock, 

 but fails to show it because it lacks the hereditary determiner 

 for pigment. 



- A PSYLLID GALL ON JUNCUS (LIVIA 

 MA C ULIPENNIS FITCH ) .f 



Since 1857 when Fitch described this beautiful little insect, 

 nothing more definite in regard to its habits has been recorded 

 than that it is found in swampy places. Thomas in 1879 said 

 that it was "found on the sweet-flag," but there is nothing in 

 his account which would indicate that it fed upon that plant. 



This past summer, however, the secret of its habitation was 

 discovered by Miss Cora H. Clarke of Boston, who made an 

 interesting collection of Juncus galls near Magnolia Village, 



*This is an abstract of a paper by Raymond Pearl, having the same 

 title and published in Practical Husbandry of Maine, Vol. VI, pp. 

 567-568, 1916. 



tThis is an abstract of a paper with the same title, by Edith M. Patch, 

 published in Psyche, Vol. xxiii, No. 1, with Plate vi. 



