80 BOTANICAL GAZETTE [JULY 
structure and growth of its plasmodium. The parasite gains entrance to the 
host through the epidermis or the root hairs, and thence from cell to cell either 
by penetrating the cell walls or by division of the host cells, each daughter cell 
containing a part of the parasite. The parasite is most abundant in the cortex, 
but is always found in the central cylinder. The infected cells hypertrophy, 
but there is no serious interference in nuclear or cell divisions until the disease 
is well advanced, when both processes are suspended. Although the author 
has not made a definite statement on this point, it appears from the general 
discussion and the drawings that the hypertrophy is most pronounced in the 
primary cortex. This is to be expected, but a careful study to determine the 
extent to which the various groups of cells are susceptible to enlargement as a 
result of stimulation by the parasite would be well worth while. The discus- 
sion of the character and life history of the parasite is excellent. 
A brief paper by HEALD" gives a description and results of inoculation 
experiments with a gall on Prosopis glandulosa. The gall is probably due to. 
Bacterium tumefaciens Smith and Townsend. 
Among the most important contributions to cecidology by American 
entomologists, we find a brief paper by CocKERELL” on a mite gall on the red 
orpine (Clementsia rhodantha Gray), one of the Crassulaceae growing in the 
high altitudes of the Rocky Mountains. The flowers ‘were aborted to a 
dense, round mass of a dark crimson-like color, consisting of excessively tuber- 
‘culated floral parts inhabited by an eriophid mite.”” The mite is similar to or 
possibly the same as E. rhodiolae Can. of Rhodiola rosea of Central Europe and 
taly. 
There is also a paper by Srars* in which the author records, figures, and 
gives a brief description of 63 species of galls from Cedar ci Ohio. These 
galls occur on 31 species of host plants representing 22 gen 
An important taxonomic paper has been published by ek 4 in which he 
lists a number of species and also describes several new species. This paper 
will enable the botanist to determine a large number of species which come to 
their attention. 
WELLs* describes 22 unreported galls from Connecticut and figures many 
of them. 
FuLLWay* gives a very interesting taxonomic paper on gall fly parasite 
as a result of studies on Mrs. ROSE PATERSON BLAKEMAN’s collection in Uni- 
« Heap, F. D., Aerial galls of the mesquite. Mycologia 4:37-38. pl. 1. 1914. 
1 COcKERELL, T. D. A., A mite gallon Clementsia. Entomol. News 25:466. 1914. 
13 SEARS, pene na The insect galls of Cedar Point and vicinity. Ohio Nat. 15: 
sia Hebi bls. 4. 
™ Fext, E. ee S aaiioks to the gall midge fauna of New England. Psyche 21: 
— ae I sig 
, B. W., Some unreported cecidia from Connecticut. Ohio Nat. 14: 
sig ak ae re 1914 
- dees. D. T., Gall fly — from California. Jour. N.Y. Ent. Soc. 20: 
274-282. 19 
