I 



MR. F. CURREY ON THE FRUCTIFICATION OF COMPOUND SPHJJRI^. 259 



doing so having been kindly accorded to me, I have done my best to avail myself of it, 

 and have now the honour of laying before the Linnean Society a " Synopsis of the fructi- 

 fication of the compound Sphcerioe of the Hookerian herbarium." In describing the natui-e 

 of the fruit, the points to l)e particularly attended to are, 1st, the number of sporidia in 

 each ascus ; 2ndly, their mode of arrangement in the ascus, i. e., whether in one row, in 

 two rows, or in a crowded and irregular manner; Srtlly, the shape of the sporidia; 

 4thly, their colour ; 5thly, their structure, i. e., whether unicellular and simple, or divided 

 by septa, Avhich latter may be transverse, or transverse and longitudinal, or even oblique ; 

 and 6thly, the length of the sporidia. The shape of the asci varies so much, not only in 

 the same species, but in the same specimen, that I do not think it a character to be relied 

 upon. 



In the great majority of cases the number of sporidia is eight, very rarely it is less, in 

 a few instances the number is sixteen, and ia a few others the number is unlimited. 



The mode of arrangement in the ascus, although tolerably constant, is not a very cer- 

 tain characteristic. There are many species in which uniseriate and biseriate sporidia 

 may be found even in the same perithecum. 



The shape and colour of the sporidia are very constant, and sure marks of distiaction. 

 With regard to colom*, however, it must be remarked that it is different at different 

 periods in the growth of the plant. For instance, in a very common species, S. ster cor aria. 

 Sow., the sporidia are colourless at first, they then assume a rich sea-green sort of colour, 

 and eventually become quite black and opaque. It might be supposed that the darker 

 colour evidenced the maturity of the plant, but I doubt if this is so, for I have seen the 

 sporidia of S. stercoraria when in theii" colourless state germinate as actively as those of 

 the darker shade. 



The structure of the sporidia when perfect is also a very safe guide, but it is to be 

 observed that there are many species in which the sporidia rarely attaia their perfect 

 state. This is particularly to be seen in some species of the division " Villosae," where 

 the sporidia when perfect are of a dark brown colour, and divided by numerous septa, 

 but where the sporidia (although attaining then- full size) more fi-equently remain simple, 

 continuous, and coloiu'less. Sphceria Corticis one of the Obtectce is another striking 

 instance of this peculiarity. The sporidia in this species are almost always colourless 

 and simple, -whereas in the perfect state (to which as far as my observations go they 

 seldom attain) they are of a dark rich brown colour and di^-ided by several septa. 



I may here observe, that it is important to distinguish between real and apparent septa; 



it is not uncommon in unicellular sporidia to find the endochrome divided into two or 



more portions, and if these portions of the endochrome touch one another, the line of 



contact often appears so like a real partition that it is not always easy to ascertain 



<- whether in fact any septum exist or not. 



The presence of miclei is a point of structure which should be noticed in describing 

 sporidia, but it is a characteristic of no great certainty, the sporidia in the same species 

 being often foimd indifferently either Avith or without nuclei, and the number of them 

 also is vai'iable. In some plants, however, as in the sporidia of S. verrucceformis, and of 

 some Hypoxyla, they are invariably to be met with. 



VOL. XXII. 2 M 



