GYMNOSPORANGIUM. 



395 



, The strikingly characteristic cleavage of the wood by the 

 overgrown elements of the medullary rays and the wood- 

 parenchyma, in the case of the twig-inhabiting form, will be 

 seen from the figures (Fig. 229). As already noticed, the 

 sporogenous cushions are generally formed on one side. After 



Fig. 229.— Two sections from a swelling on a Juniper-bi-anch. a. From the 

 middle of the swelling ; the rind under the spore-cushion is much thickened, and 

 the wood is much broken up by tnicts of parenchyma. 6, Section from 2 cm. 

 under a ; abnormal development of parenchyma in the wood has begun in the 

 outer year-rings. (After Woernle.) 



the shedding of the cushion, a corky layer arises in the paren- 

 chyma undcrnoatli it, and so a bark-scale is produced. 



Gymnosporangium sabinae (Dicks.). (Britain.) The mycel- 

 ium hibernates chietiy in Ji'Jiijyerus Sahiiia (Savin), and induces 

 swellings on the twigs. It also occurs on Jun. Oxyccdrus,^ 



' I found this host-species near Fiunie. 



