1905] Fernald,— A New Arabis from Quebec 31 
We may say that it is a law of plant building, in certain species, that 
when a certain arrangement is realized the production of stipule and, 
eventually, absciss-layer must succeed. When therefore a very simi- 
lar arrangement is attained in the compound leaf of these species, 
stipels and absciss-layers follow almost perforce, by the operation of 
the same structural law of sequence. The repetition of conditions 
not being perfect, however, the result is not certain in the case of 
stipels: many compound leaves lack them. But as we have seen, 
the absciss-layer appears highly constant. ‘The passage of characters 
from location to location in these instances is comparable to that 
exhibited by peloric flowers, and by the anomalous forms which stand 
at the beginning of this paper as a text. Stipels and petiolular 
absciss-layers, characters of many groups of plants, seem to be effects 
of a principle which for lack of a better expression I have here called 
morphic translocation. 
THE Ames BOTANICAL LABORATORY, North Easton, Massa- 
chusetts. 
A NEW ARABIS FROM RIMOUSKI COUNTY, QUEBEC. 
M. L. FERNALD. 
On July 18, 1904, an unfamiliar Arabis was collected by Mr. J. 
Franklin Collins, and subsequently by the writer on one of the 
headlands which characterize the south shore of the River St. Law- 
rence at Bic, Rimouski County, Quebec. The plant, growing with 
Cerastium alpinum, var. beeringianum, Saxifraga caespitosa, Woodsia 
oregana, and other high-northern or northwestern species, on dry 
calcareous ledges, was strikingly canescent, and, with its strongly 
refracted pods and white petals immediately suggested Hornemann’s 
A. Holboellii of Greenland, and its numerous Rocky Mountain 
allies. 
A careful study of the Greenland plant and of authentic speci- 
mens or the original descriptions of its known American representa- 
tives fails, however, to identify the strange Arabis from the St. Law- 
rence. In general habit it resembles many of these species, but its 
nearest affinity is perhaps with the Greenland 4. Ho/boed/i itself, from 
