18G THE .TOUllXAL OF BOTANY 



seed of a typical plant of Gussonel individuals .showing numerous 

 beaked aclienes as well as others with broad and serrate wings— a 

 result which, in liis opinion, confirms his inclusion of the Calabrian 

 Calendula (C stdlata var. crocea Guss. PL Ear.) in C. Gussonei, in 

 spite of the deeply serrate wings of the outer achenes of the former. 



In spite of his long study of the brilliant CalcndiilcB that in 

 winter and spring adorn the rocks and fields of Sicily, Dr. Lanza has 

 failed to discover how this extraordinary heteromorpliism in the fruit 

 can in any way help the survival or extend the area of the species. 

 He concludes his discussion of that subject by saying that " the 

 heteromorphism of this genus is simply morphological not biological." 

 Tliis is a counsel of despair which need not be accepted literally ; let 

 us rather confess our ignorance of the utility of the heterocarpism 

 without proclaiming it to be useless. 



Natural cross-fertilisation between different individuals, whether 

 of the same variety or not, proves to be more difficult than one would 

 suppose ; as, although the flowers are proterogynous, the interval 

 between the maturity of the stigma and the emission of pollen 

 is extremely short, lasting only an hour or two in the annual, and 

 about half a day in the perennial s})ecies ; while the relative position 

 of anthers and stigmatic branches ensures immediate self-pollination 

 after that interval. 



There is one unexpected omission in this monograph which leaves 

 a free field for investigation by those who come after. C. offici- 

 nalis L., the garden plant, is passed over in almost complete silence. 

 Whatever may be the origin of the forms in cultivation, that origin 

 is not known ; the forms cannot be identified with or definitely 

 referred to any of the spontaneous Calendi(l(p that are known at 

 present, nor is it probable that in future there will be discovered any 

 new species which could be regarded as the true, or at any rate the 

 sole, ancestor of ojficiualis. 



We must conclude with the strongest possible recommendation to 

 to British botanists of a study of Dr. Lanza's monograph. 



C. C. Lacaita. 



The Wheat Flant : A Monograph, By John Perciyal, M.A., 

 F.L.S. 8vo, pp. X, 463, tt. 228. Duckworth: London, 1921. 

 Price £3 6s. U, 



This attractive-looking volume embodies the results of twenty 

 years' intensive study of our most important food-crop. The authin- 

 has critically examined living specimens from all parts of the world, 

 and nearly two thousand forms have been grown annually side by 

 side, and their morphological characters in the young and mature 

 states, as well as their habit of growth, ripening period, suscepti- 

 bility to the attacks of fungi and other characters, have been in- 

 vestigated and compared. 



The subject-matter is divided into two parts. Part I (to 

 page 143) is an exhaustive botanical study of the wheat plant from 

 the grain, its germination and development, to the formation of 



