894 BULLETIN DE L'HERBIER BOISSIER. (2) 



are usually tufted. On the other hand, two species of Arenaria with long 

 cylindrical capsules, viz., A. Guicciardii Heldr. and A. purpurascens 

 Ramond, may by regarded as Connecting links with the normally 3-styled 

 species of Cerastium. In Cerastium the capsule may be said to be always 

 more or less elongated, while in Stellaria and Arenaria it is characleris- 

 tically ovoid or oblong. The generic nanie was first applied by Dillenius 

 to the plant now known as Cerastium glomeratum. 



The cardinal character which seems to suggest the grouping of species 

 in subgenera is the structure and number of the leeth formed by dehis- 

 cence of the ripe capsule. Whether the capsular teeth are opposite the 

 sepals or alternate with them is a more important character than the 

 fact of the gyncecium being isomerous or meiomerous in relation to the 

 segments of the calyx. There is therefore greater reason for keeping up 

 the genus Malackium than for referring Cerastium trigynum Yill. to 

 Stellaria, where it was first placed by Linneeus. The same character 

 satisfactorely serves to distinguish Spergula from Spergularia. 



The most characteristically defined group in Cerastium includes those 

 species in which the teeth of the capsule afler dehiscence are finally 

 circinate-convolute. In none of the allied gênera does this peculianty in 

 the capsular teeth occur. But it is to be noted that in all the species refe- 

 rable to this group the ripening capsule, while increasing in length, 

 does not become curved, except in C. Armeniacum, where it is conside- 

 rably curved, and more than half exserted from the calyx. If, without 

 regard to the number of teeth (whether six or ten), those species in 

 which the teeth are finally circinate-convolute are included in the group 

 defined by Seringe as the section Strephodon, there only remain in the 

 group defined by Bartling as the section Dichodon two well-known 

 species, C. trigynum and C. anomalum. To these may, however, be added 

 C. mauretanicum Pomel, and C. melanandrum Maxim. It may further be 

 pointed out that in C. trigynum and allied species the capsule is never 

 curved, which serves with other characters taken into considération to 

 separate them from the large group of which C. glomeratum and C. arvense 

 are well-known examples; a group in which the character of the 10-den- 

 tale capsule is normal. 



As the ripe capsule dries, its striated character becomes apparent ; and 

 while in the large majority of the species the distinct nerves are equal to 

 the number of the teeth, in a few species intercalary nerves are quite as 

 readily made out, so that in these the nerves are twice the number of 

 the teeth. Only in spécimens of C.persicum have I noticed that the stria- 



