120 ENGLISH BOTANY. 



stomates. Similar bodies liavc been described by Dr. Dickie in tlic leaves of Pedicu- 

 lari's, and Professor Busk discovered tbcm in small numbers in the leaves of IIlj>puns 

 vulgaris. On the one hand, they undoubtedly resemble the stellate hairs found in 

 Capsclla Bursa Pastor is and other Cruciferous plants, whilst their resemblance to some 

 of the compound forms of stomates has struck other observers. M. Ad. Chretien, in a 

 paper in the Comptes Rendus, vol. xl., is disposed to regard them as independent 

 organs, and calls them " cystides." He thinks, however, that they are rather modifi- 

 cations of stomates than of hairs. These curious organs demand more attention than 

 they have hitherto received, and would probably repay the microscopist by further 

 researches amongst the species of plants in which they exist. 



Sub-Species II.— Callitriche platycarpa. Kiitz. 



Plate MCCLXXII. 



Reich. Ic. Fl. Germ, et Helv. Vol. V. Tab. CXXIX. Fig. 4748. 

 C. stagnalis, Hegelm. Monogr. p. 58 (non Scop). ?). 



Pollen grains subglobose. Fruit subsessile or shortly stalked, as long 

 as or a little shorter than broad, subcordate, flattish on the faces ; mar- 

 ginal furrows rather deep; margins of the lobes rather broadly and 

 sharply keeled. Styles at length reflexed, persistent. 



In ditches, ponds, and on mud. Common, and generally distributed. 



England, Scotland, Ireland. Perennial. Spring to Autumn. 



Very similar to C. vernalis, but with the fruit nearly twice as large, 

 ■^ inch long, and considerably broader in proportion, with a deeper 

 furrow round the margins, generally with a slight tendency to become 

 stalked when mature, and of the same pale colour as that of the last ; 

 the leaves are very similar, and the floating rosette is almost alwaj's 

 present; when the plant grows out of the water the leaves are 

 frequently all obovate, but smaller than Avhen they are floating. 



l3r. Hegelmaier considers that C. stagnalis of Scopoli, which has the 

 lobes of the fruit divaricate, is not different from the C. platycarpa of 

 Kiitzing, in which the lobes are subparallel, and in that case the name 

 C. stagnalis must be adopted for this subspecies. The form with 

 divaricate lobes has not been observed in Britain, so fai* as I am aware. 



Large-fruited Water Starwort. 

 French, Callitriche a fruits larges. German, Breitfrilchtiger Wasserstem^ 



Sub-Species III. — CaUitriclie hamulata. Kutz. 

 Plate MCCLXXIII. 



Reich. Ic. Fl. Germ, et Helv. Vol. V. Tab. CXXX. Fig. 4749. 

 Billot, Fl. Gall, et Germ. Exsicc. No. 356. Hegelm. Monogr. p. 5G. 

 0. autumnalis, Kiltz. Reich. Fl. Germ, Excurs. p. 754 (non Linn.). 

 C. pedunculata, jS, sessiUs, Bab. olim. 



Pollen grains subglobose. Fruit sessile or subsessile, as long as or a 



