A Monograph of the Myxogastres. 27 



possible, yet in so difficult a subject, the modus operandi alone 

 would enable others to follow along the same lines. In the 

 present state of knowledge, the markings usually present on the 

 epispore appear to be constant within narrow limits, are often 

 very characteristic, and of value as one factor in the discrimina- 

 tion of what we at present consider to be species, nevertheless I 

 wish to express the strongest dissent to species founded on spore 

 characters alone, or indeed on any one, character. Rostafinski 

 was the first to use spore characters in a specific sense. It is 

 important to bear in mind, that the apparent nature of spore 

 ornamentation depends entirely on the amount of magnifying 

 power used; the complex epispore of Trichia affinis appears 

 only as a confused series of minute irregular projections under a 

 quarter-inch objective, consequently there is no absolute char- 

 acter in the spore unless a uniform magnifying power is agreed 

 upon. The objective used in determining the nature of the 

 epispore as described in the present work is a T V oil immersion, 

 which gives a magnifying power of 1200 diameters. So far as 

 the synonymy is concerned, I can only repeat in substance what 

 I have written on a previous occasion in connection with the 

 same subject. I have not included the synonymy further back 

 than Rostafinski' s Monograph, unless justified by the presence 

 of type or authentic specimens. Rostafinski has given syno- 

 nyms dating from the time of Micheli (1729), but on referring 

 to the earlier descriptions, I realize my weakness, in not being 

 able to reconcile the wonderfully brief descriptions, and equally 

 crude drawings, with modern species, which in many instances 

 require a magnifying power of 1000 diameters for their deter- 

 mination, hence I wish to be clearly understood that the 

 synonyms headed " Rostafinski's Synonyms," are copied from 

 Rostafinski's Monograph without any attempt at corroboration. 

 I feel certain that nearly one-third of Rostafinski's work would 

 not have been sacrificed to synonyms unless they mean some- 

 thing more than I have been able to discover, hence I have not 

 felt justified in ignoring them altogether. 



