At A is illustrated one of the stems of the Poppy =Peronospora= emerging from the leaf, enlarged seventy-five diameters.  The fungus of the Poppy is very much more branched than that of the Potato, and every minute branchlet carries a spore.  To save confusion, a large number of spores are omitted from the branchlets in the illustration, and the branches growing from the stem both before and behind are for the same reason left out.  At B a tip of a single branch is shown further enlarged to four hundred diameters.  The spores in the Poppy fungus are unusually large and numerous:  an infected plant will throw off many millions of such spores.  All the putrefactive spawn of this fungus is inside the host-plant; cure, therefore, is difficult.  This disease, like every other plant disease, is always at its worst in ill-kept places where red field Poppies are abundant.  Field Poppies are often sown with unclean corn.  As prevention is better than cure, all we can advise is, buy the best and cleanest garden and field seeds, cultivate in the best way, and look out for and burn, or deeply bury as soon as detected, all disease-stricken plants, whether wild or cultivated.  When diseased plants of any sort are left to decay on the refuse-heap, it is the most certain way of propagating a plant disease for the next year.

==Diseases of Violets.==—­Violets are subject to fungoid diseases, both in spring and autumn.  The disease of autumn is caused by the brown =Puccinia violae=, allied to the =P. graminis= of Corn and to the =P. malvacearum= of Hollyhocks and various malvaceous plants.  The =Puccinia= of Violets has its yellowish or orange-coloured stage; it is then known as =Trichobasis=, or =Uredo violarum=.  In spring and early summer Violets are often badly affected by a fungus named =AEcidium violae=, which is apparently identical, however, with =Puccinia violae=.  This disease attacks leaves, stems, and sepals, and it is best examined on the leaves.  In this position it is seen to consist of a considerable number of minute yellow pustules, each pustule less in size than a pin’s head, and all congregated into one flat circular mass of about a quarter of an inch in diameter.  This pest is very frequent on the Dog Violet, but it is perhaps equally common on the Sweet Violets of our gardens in early spring, and it not infrequently spreads to other species of =Viola=.  One of the most destructive pests of Violas is found in =AEcidium depauperans=, so called because its effect is first to starve and attenuate, and then to totally destroy, plants of =Viola cornuta=.  It is a close ally of =Ae. violae=, but it differs in having its minute cups or pustules irregularly distributed all over the green parts of the host-plant instead of being congregated in circular patches, as in =Ae. violae=.  Our illustration shows, at A, a small portion of the stem of =Viola cornuta= attacked by =AEcidium depauperans=.  The minute pustules are seen (natural size) distributed