232 PHYLUM VII. CARPOMYCETEAE 
(k) Make very thin cross-sections of several of the gills and 
carefully mount in water or alcohol. Note the layer of spore- 
bearing cells (hymenium), with basidiospores borne upon little 
stalks. 
(l) Examine the pores of fresh polypores in transection, 
looking for the basidia and basidiospores in the pores. 
(m) In like manner make transections of Prickly Fungi, 
Coral Fungi, and Leathery Fungi, but in these look for basid- 
iospores on the outer surface of the sections. 
Cass 16. TELIOSPOREAE. Tue Branp-Fonat 
392. Here are collected a considerable number (4200 
species) of extremely parasitic fungi, certainly related to 
the fungi of the two preceding classes. On account of 
‘their excessive parasitism they are structurally much re- 
duced and degraded and this has served to hide their true 
relationship. 
393. The plant body consists of branching septate 
filaments which run through the green tissues of higher 
plants, eventually producing usually erumpent spore 
clusters (sori), but no definite spore fruits (perithecia, or 
apothecia). Conidia of one or two kinds are usually 
present, and precede the formation of teliospores. 
394. The Rusts (Order UREpDINALES) are minute, 
parasitic, greatly degraded fungi 
which grow in the tissues of higher 
plants. 
395. A common Wheat rust 
seit Ses ih baal (Puccinia graminis) may be taken 
of aeciospores and pycnio- AS an illustration of the order. It 
rove is common wherever wheat is 
grown, and often greatly injures and sometimes entirely 
destroys the crop. Its round of life shows four well- 
marked stages, as follows: (I) In the spring clusters of 
minute yellowish cups occur on the leaves of the 
