1916] Gilkcij: A Rci'isioii of flu TubcraUs of California 337 



careful study possible was made of a large series of these, and in no 

 ease was there any indication of external communication from the 

 hymenium. 



A cross-section of the ascocarp suggests the structure of Choiro- 

 myccs, but descriptions and illustrations show tlic hyiiiciiiiiiii of 1he 

 latter to consist of long, irregularly Ix'iit bands, the lialves running 

 more or less parallel and the ends often joined, the space between the 

 free tips of the two rows of palisade filled with hypluil tissue. The 

 sterile veins separating the bands appear irregular in shape and gen- 

 erally much wider than the bands. In tlie Californian specimens, the 

 whole ascocarp is made up internally of an elaborate system of very 

 narrow folds densely covered with hymenium. Tlie folds, which form 

 the sterile veins, are remarkably regular in width. These are often 

 fitted so closely together that the free ends of the two rows of asei are 

 nearly or quite in contact, but in places the folds are less closely asso- 

 ciated and leave comparatively wide, open chambers. Sometimes the 

 folds are united at points, closing the chambers, but as a rule they are 

 unconnected and can be separated for long distances through the asco- 

 carp. The canals, when wide, are generally irregular in shape, due 

 to inward projecting, short branches of the venae internae. The 

 spores are smaller than for any described species of Clioiromyces, and 

 are globose-ellipsoid instead of globose, while the asci are cylindrical 

 rather than club-shaped. The structure of the interior comes near 

 that of Geopora, but the glabrous surface, sculptured spores, more 

 minute and compact folding, uniform veins originating from the sub- 

 cortical layer rather than from the infolding of the cortex as they 

 are formed generally in Geopora, and the much more common presence 

 of short chambers, seem sufficient basis for the separation of the two. 



While Hydnotryopsis differs from Hydnotrya in the absence of 

 venae externae and the presence of a conspicuous system of venae in- 

 ternae, the general arrangement of empty canals and chambers lined 

 with hymenium in regular palisade, the walls of the canals apparently 

 formed by more r.ipid internal tlum external growtli of the ascocarp, 

 is like that of Hydnotrya; and the two have apparently reached the 

 same stage in parallel lines of development. Though little preserved 

 material exists from which to describe the genus, it seems sufficiently 

 distinct from all other genera of the Tuberales to justify its position. 

 It is to be hoped, however, thai fiirthci- collections and data may be 

 obtained. 



