1^16] Yates: Histology of Californian Boletaceae 257 



swollen ends of liyphae, 4 to lO/j. in diameter. Below these swollen 

 hyphae tips is a layer formed of densely interwoven hyphae, 2 to Sfi 

 in diameter. The rind is dark brown in color. The hyphae making 

 up the rind arise as branches from the hyphae of the context. The 

 context is made up of hyaline hyphae, 4 to 8fx. in diameter, which lie 

 parallel to each other and to the long axis of the stipe. Glands like 

 those previously described under the Californian form are found on 

 the surface of the stipe (pi. 25, fig. 29). 



Rostkovites calif ornicus (Murrill) 



Plate 21, figure 8 



The plants referred to under this name were sent in by Mr. F. H. 

 Bolster of Grass Valley, California, and were then referred to Dr. 

 "W. A. ]\Iurrill, by whom they were recognized to be a new species, 

 which was described by him as Rostkovites calif ornicus in Mijcologia, 

 Vol. VII, No. 1. 



They were sent to Dr. Murrill in the dried condition, but the speci- 

 mens were accompanied by notes made by myself from the living speci- 

 mens. Specimens of R. calif ornicus are filed in the University of Cali- 

 fornia Herbarium under No. 251. 



Rostkovites californicus may be described as follows. The pileus 

 is 6 to 9 cm. broad, convex to plane, surface brown, smooth, subto- 

 mentose, viscid when fresh, margin even. The context is fleshy, light 

 yellow, unchanging, taste mild. Tubes adnate, yellow, -t to 6 mm. long. 

 Mouths large, angular. Spores obhmg-ellipsoidal, 7 to 8 by 3.5 to 4/*, 

 brown and smooth. Stipe 3 to 6 cm. long and 1.5 to 2 cm. thick, equal 

 or slightly enlarged at the base. Surface yellow with black dots or 

 granulations. Context yellow, unchanging, somewhat fibrous at the 

 base. 



The plants referred to R. californicus differ from R. granulatus es- 

 pecially in the subtomentose surface of the pileus. The spores are 

 also slightly smaller. 



Histology 



The surface of the pileus is covered with long hairs, 8 to 10/u. in 

 diameter and 200 to 250/i, in length. These hairs are embedded in a 

 purpli.sh jelly which, with the hairs, forms a distinct cuticle or rind. 

 Beneath the hairs is a tissue made up of densely intertwined hyphae, 



