CHAPTER V. COMPARATIVE REVIEW. HYMENOMYCETES. 303 



the hymenium in Coprinus, while maturing and when mature, is covered with 

 irregularly 3-5 angled prismatic almost isodiametric cells of uniform height and with 

 pellucid contents. The much narrower basidia are inserted without interruption 

 between the corners of these paraphyses-cells, alternating therefore with them, and it 

 is only rarely that the corners of two paraphyses meet together (Fig. 139). 



Other formations occur not unfrequently, different from these paraphyses-forms 

 and in certain cases at least close beside them, which are generally distinguished from 

 them by the circumstance that they stand out as large unicellular structures far 

 above all others on the hymenial surface. As they are often inflated in appearance 

 in the fleshy species LeVeille* named them cystidia; Phoebus called them specially 

 paraphyses. 



The cystidia according to present accounts have been found in species of all the 

 groups except the Tremellineae, Clavarieae, and Hydneae, but so distributed that 

 their presence or absence and their relative frequency of occurrence vary according 



FIG. 139. Coprimis micaceiis, Fr. a a thin longitudinal section through the upper surface of a lamella, the 

 liasidia distinguished by their turbidly granular contents and springing from the subhymenial cells between 

 pellucid inflated paraphyses ; f a cystidium. b surface-view of the hymenium. The intercellular space between 

 two paraphyses to the left above appears by a mistake in the woodcut, but was not shown in the drawing from which 

 the woodcut was taken. Magn. 390 times. 



to the species within narrow cycles of affinity. While they are wanting, for instance, 

 in most of the non-fleshy Polypori, they are found in Polyporus igniarius and Trametes 

 Pini ; while they are abundant in most Coprini they occur rarely or not at all, according 

 to Brefeld, in Coprinus ephemeras. They originate like the basidia in the subhymenial 

 tissue and their position is the same as theirs ; but sometimes, as in Trametes Pini 

 and Lactarius deliciosus, they terminate special branches of hyphae which ascend 

 to the hymenial surface from the interior of the trama without directly bearing 

 basidia also. They are sometimes scattered without order over the hymenial surface, 

 more frequently they are found on the free margin of the hymenial processes, especially 

 on the edge of the lamellae in the Agaricineae. Their number is usually small 

 compared to that of the basidia, often very small ; but in species of Stereum which 

 LeVeiHe" named Hymenochaete 1 (S. rubiginosum and S. tabacinum) the hymenium, 

 owing to their presence, has the appearance of being covered with bristly hairs. 



1 Ann. d. sc. nat. ser. 3, V (1846), p. 150. 



