46 DISEASES OF CROPS. 



discovered by a well-known fungologist, Mr. W. Phillips, 

 F.L.S. {Gardeners' Chronicle, July 14th, 1883), on Allium 

 schcanoprasum (chives). The fungus covers the leaves 

 and flower stalks (Fig. 18 A and B) with brown spots. 

 These spots are caused by sori, or masses of spores, etc., 

 which ultimately rupture the epidermis of the host-plant. 

 Each sorus (Fig. 18 0) is composed of a thickly matted 

 mycelium, which ramifies among the tissues of the host ; 

 and gives rise to a large number of brown bodies (more 

 or less club-shaped), which are morphologically spores, 

 although unlike the conidia of other fungoid growths. 

 These spores are called teleutospores, and are true resting- 

 spores. The teleutospores of the garlic rust are of two 

 kinds (Fig. 18, 1 and 2). One is divided by a transverse 

 septum, and the other is not so divided. These spores are 

 capable of hibernating for several months. 

 Prevention. — Burn all infested refuse. 



(5) The Parasites of Parsnips {Pastinaca sativa). 



The Parsnip Leaf Miner {TepJiritis onopordinis). 

 The members of the genus Tephritis are lively little flies; 

 and the species about to be described is one-sixth of an 

 inch long, of a brown colour, with green eyes, and two 

 transpai-ent wings. The female lays her eggs within the 

 cuticle of the parsnip leaves, where they are hatched, pro- 

 ducing little pale-green maggots, which cause large blisters 

 upon the leaves. These blisters ultimately cause the com- 

 plete decay of the leaves. The pupa of this fly is of a 

 yellow-brown colour, and is found on the leaves of the 

 parsnip and in the earth. 



There are several broods during the year. The pupge last 

 produced, hibernate in the soil until the following spring. 



Prevention. —(1) Curtis recommended a dressing of tar 



