CAEOMA. 419 



leaHess shoots on Thi'Jojisis (Ivh(J)r(ita in Japan, whence they were 

 sent to me (Figs. 25-4 and 255). One example (not tigurtMl) was 

 as large as a young child's head. 



The shoots of the witches' brooms are furnished with vascular 

 bundles and possess a parenchyma rich in starch-content. 

 Each branch of the deformed shoot termi- 

 nates in a hemispherical saucer-shaped 

 vacoma- cw'&h.ion, at tirst covered over by 

 the epidermis, l)ut with no peridium. The 

 (Ytco?n«-discs are at tirst brown, but alter 

 the epidermis bursts and rolls back, the 

 yellow dusty spores appear. The spores ^^^^Fif- pori^n"oT'the'*'^re- 

 arise serially from very short basidia ; they ceding figure enlarged to 



J J y •/ show the CfieowiK-discson the 



are yellow and have striped membranes. ends of twigs, (v. lubcuf 



The witches' brooms also exhibit marked 

 hypertrophy (Fig. 254). In the supporting branch both wood 

 and bark are considerably increased. Large medullary rays occur 

 in the wood, and nests of thin-walled parenchyma are interpolated 

 between the regular tracts of tracheae, so that the general 

 arrangement resembles that shown in juniper by W('>rnle's 

 researches on Gymnosporaiujiam. The parenchymatous groups 

 of cells in the wood appear to the naked eye as brown spots. 

 They are permeated by a vigorous intercellular mycelium, which 

 sends off large haustoria into the adjacent cells. 



Caeoma laricis (We.steiiil).i On needles of Larir. (Britain.) 



C. orchidis A. et 8. On orchids. (Britain.) 



C. chelidonii Magn. On Chelidonium majus (U.S. America). 



C. fumariae Lk. On Conjdalis. 



C. euonymi ((hnel.). On Euonymus eiiropaeus (Britain). 



C. confluens (Pers.). On Riles alpinum, R. rubrum, etc. 



C. nitens (C. luminatmn) is the well-known Blackberry-rust so common 

 in the United States. It is probably a form of Puccinia Peckiana.'^ 



C. aegopodii (Rebeiit.). On Aegopodkim Podagraria and Chaeroph>jJlnm 

 iiromadcv./it. 



C. ligustri (Rabh.). On Ligustritm vulgare. 



C. ari-italici (Diiby). On Anim maculatuvi. 



C. alliorum Link. On Allium ursinum, A. olemceum, etc.'' 



C. saxifragae Strauss. On Saxifraga gramdata? 



C. mercurialis QIart). On Merciirialis perennis.^ 



' Tiiis and most of the other species are only stages of some Mdampsom. 



-Clinton, Botanical Gazette, 1895, p. 116. 



•' These three species are given as British in Plowrighfs 'Uredineat.' (Edit.) 



