164 GENETICS [BoT. Absts., Vol. VIII, 



flicting results, Correns finding strict matrocliny and Baur the production of piebald varie- 

 gated plants as well as white and green. The mutation coefficient, "green" to "white," is 

 0.01 per cent, such mutations probably occurring in the somatic cells before the flower appears. 

 Three methods are possible, (1) vegetative mutation, (2) mutation in the gametes, and (3) 

 the appearance of variegation as an intermediate character between 2 races. The latter 

 possibility is illustrated by the author's 2nd type of variegation. A plant of this type 

 appeared by mutation in 1918. Selfed green twigs, variegated twigs, the cross, variegated X 

 green, and the cross, variegated X a constant chlorina type from Oe. suaveolens X Oe. Hookeri, 

 all gave green progeny, the latter heterozygous for a chlorophyll factor. This type consti- 

 tutes an intermediate race. Its characters in so far as they may be called specific are desig- 

 nated by the writer as "taxonomic anomalies." — Corren's hypothesis that white variegation 

 is due to a disease condition is summarily dismissed and the alternative hypothesis of a 

 special condition of the gene for the development of chlorophyll for each cell complex, 

 advanced. The white sub-epidermal layer in Corren's Arabis pallida pseudoleucodermis, for 

 instance, appears as the expression of a semi-latent gene for normal green pigment. — In 

 closing the author says, "La verite est en marche; rien ne I'arretera." [See also Bot. Absts. 

 8, Entry 1107.]— Paw Z A. Warren. 



1122. TiscHLER, G. [German rev. of: Florin, Rudolf. Zur Kenntnis der Fertilitat 

 und partiellen Sterilitat des Pollens bei Apfel und Birnensorten. (On the fertility and par- 

 tial sterility of the pollen of different varieties of apples and pears.) Acta Horti Bergiani 7: 

 1-39. 1920 (see Bot. Absts. 5, Entry 1503).] Zeitschr. Bot. 12: 687-688. 1920. 



1123. Van Denburgh, John. A further study of variation in the gopher snakes of western 

 North America. Proc. California Acad. Sci. 10: 1-27. 2 pi. 1920. — A study of the varia- 

 tions of number of gastrosteges, dorsal color pattern blotches, and scale rows has revealed 

 the existence of 7 geographical races of the western North American gopher snakes, Pituo- 

 phis. On the basis of number of gastroteges 2 subspecies were formerly recognized. Those 

 having the lower number, P. cantenifer cantenifer, occur in the cool northern coast and adja- 

 cent interior regions extending to middle California. The number of gastroteges increases 

 in the southern regions where is found P. c. annectens. Within these subspecies geographic 

 variation in color pattern exists, the coast forms having a higher number of blotches than the 

 interior forms; P. c. heermanni is the northern interior form having fewer color blotches 

 than the coast form of the same latitude. The same distinction is found between coast and 

 interior forms of the southern group. The interior form here is designated P. c. deserticola. 

 The number of scale rows also shows geographical variation permitting a further subdivision. 

 The northern and southern divisions named above fall into 2 groups while the snakes of 

 Lower California, Utah (rutilis), and Arizona (stejnegeri) form 3 different groups, the latter 

 2 being subspecies, that of Lower California a true species, P. vertebralis. The author has 

 thus divided 3 groups into 7 on the basis of geographic variation of at least 3 characters. A 

 key for the identification of the 7 groups is given. — J. L. Collins. 



1124. Vries, Eva de. Versuche iiber die Frucht- und Samenbildung bei Artkreuzungen 

 in der Gattung Primula. [Study on fruit and seed formation in species crosses of the genus 

 Primula.] Rec. Trav. Bot. Ne^rland. 16: 63-205. 1919.— Study in detail on seed and fruit 

 formation in species crosses between Primula acaulis, P. Sibthorpii, P. elaiior, P. Juliae, 

 P. Auricula, and P. hirsuta with special reference to self and cross-pollination as related to 

 heterostylism. Short-style X short-style and long-style X long-style represent illegitimate 

 unions in author's classification, while long-style X short-style and its reciprocal are desig- 

 nated legitimate. Illegitimate unions are of two kinds — those from selfing and those derived 

 from crossing plants of either the same or of different species, but with the same type of style. 

 When protected against insects, there is no self-pollination in P. acaulis. In profuse-flower- 

 ing stocks of P. elatior, spontaneous selfing takes place in short-style, but very rarely in long- 

 style plants. Artificial self-pollination in case of P. acaulis and P. elatior give different 

 results with the two style types. Long-style P. acaulis gave about 25 per cent fruits as 



