INTRODUCTION TO CRYPTOQAMIC BOTANY. 831 



to have thousands of such matters submitted to them in 

 the course of the year with the expectation that a distinct 

 name shall be assigned to every one, however obscure and 

 devoid of interest. It was remarked by Fries, with his usual 

 acuteness, that imperfect mycologists too often pass over the 

 objects which surround them of real interest, while they col- 

 lect and number every dead twig or stipule that has the most 

 microscopic black speck. The structure of the greater part 

 of them is much the same : an obscurely developed perithe- 

 cium, minute sporophores, and microscopic spores, often differ- 

 ing in nothing more than microscopic dimensions. Now, even 

 if these were uniform in size, which is very far from being the 

 case, microscopic measurement is very uncertain when bodies 

 less than the five thousandth part of an inch^are in question, 

 and some of them are at least three times as small. No accu- 

 racy, indeed, can be obtained without the best instruments, and 

 very skilful manipulation. But besides this, it is quite certain 

 that a large portion of the so-called species of Phoma, LeiJto- 

 stroma, Diplodia, Hendersonia, Cytispora, Septoria, &c., are 

 mere cases of dualism, and the same may, without much chance 

 of error, be predicated of those cases, as Dilopliosporiurti, 

 Ncottiospormm, and Pestalozzia, where the objects are of 

 some interest on account of their curious appendages. All, 

 indeed, are interesting so far as ascertained dualism is con- 

 cerned, or as far as there may be a prospect of showing 

 that they are the spermatogonia or pycnidia of ascophorous 

 species. One of the most interesting cases, j)erhaps, which has 

 occurred is that of the production from the same hymenial 

 surface of distinct asci and the double spores of Diplodia 

 (Fig. 60, c). The so-called species are as multitudinous as the 

 Uredines ; and even supposing them to be autonomous, there 

 is no doubt that they ought to be very greatly reduced ; but 

 the fact is, that the determination of a very large portion of 

 them is altogether empiric. No man would spend a life in the 

 study of objects of so little interest ; and if every Splueria has 

 its pycnidia, it is at once obvious that there must be more than 

 a thousand productions of the kind, which have a claim to dis- 

 tinct individuality, so far as the Sphwronemei alone are con- 



