250 REVIEWS. [August, 



fronds. In H. Wilsoni it is less sessile, and diverges with a curvature 

 from the frond (as well represented in ' English Botany,' Suppl. t. 2686. 

 Compare with H. tunhridgense, E. B. t. 163). Again, though H. Wilsoni 

 has the valves of the involucres of a firmer texture, when they expand in 

 age they are ynore convex in form, the sides turning up more, so that the 

 valves almost become semi-cylindiical. In S. tunhridgense the texture of 

 the valve is scarcely different from that of the frond, yet they retain in age, 

 and when expanded, more of their original flattened or slightly convex 

 form. Now when 1 see such characters invariably accompanied in the one 

 case with entire margins, in the other with deeply serrated or almost spinu- 

 lose ones, I cannot do otherwise but look upon them as distinct as any 

 two Fenis can well be. . . ." 



On p. 204 of the same Report there is a description of a new 

 species of Desmidiacea, which has been named Tetrachastrum 

 mucronatum. The specific characters are the following : — " Frond 

 longer than broad, ends rounded, having a slight central con- 

 cavity ; the end lobe has its lateral projections terminated by a 

 mucro; basal lobes broadly and bluntly triangular, having at 

 their margin at each side either one, two, or three mucro-like 

 spines ; empty frond punctate, the puncta scattered. 



" Symbol : a, b, c, parallel. 



" Locality : bog, near Carrickmore, county Tyrone. 



" Measurement : length of frond -^ ; greatest width, ^4-^ ; 

 width of neck, -j}-^; diameter at constriction, -5-^; greatest 

 depth, ^4-0 of ^^ inch." 



Note. — There is appended a coloured figure of this new dis- 

 covery. 



Welter Zus'dtze zu meiner Flora der Pfalz. With a Lithograph. 

 [Further Additions to the author's Florc^ of Pfalz.) 



In this additional sheet the author describes what he calls a 

 hybrid (bastard) between Epilobium palustre and E. parviflo- 

 rum. The description of this intermediate form given by the 

 learned professor, amounts to twenty lines of such Latin as 

 botanists employ : and as it might not be interesting enough to 

 our readers to warrant putting it in print, either in the original 

 or in a translation, which could only be, like the plant, a hybrid, 

 between Latin and English, repulsive to some, and unattractive 

 to many. If any reader of this desires to see it, we will under- 



