Phytelephas 



( 196 ) 



Phytoptus 



PHYTELEPHAS. 



Dwarf, spineless Palms (irrcl. Palmse), all needing 

 a stove temperature. They are of easy culture 

 when a liberal supply of water and free drainage 

 are given. Propagation, by imported seeds, sown 

 in strong heat. Soil, loam three parts, cow manure 

 and leaf mould one part each, with sand. The 

 hard seeds furnish the popular vegetable ivory 

 so much used by turners in the manufacture of 

 toys, buttons, and useful domestic articles. When 

 nicely polished the appearance is almost equal 

 to that of animal ivory. 



Principal Species : 



macrocarpa, 6', Ivs. 15' to 20' long, pinnate, 

 arching. Ivory Nut Palm. 



Other Species : 



microcarpa, stemless, Ivs. 20' to 24' long. 



PHYTEUMA. (HORNED RAMPION.) 

 Ornamental hardy perennials (prd. Campanu- 

 lacese), of value for borders or rockwork. Propaga- 

 tion, by division or by seeds in spring. The 

 smaller species, such as comosum, do best in well- 

 drained but moist crevices in the rockery in a 

 gritty soil ; the others grow in common soil. 



Principal Species : 

 Balbisii, 6", sum., wh. 

 comosum, 4", Jy., bl. 

 Halleri, 6", My., vio. 

 hemisphfericum, 1', Jy., 



bl. 



humile, 4", Jy.,bl. 

 hmonifolium, 2i', Je., bl. 



(syns. strictum and 



virgatum of Loddiges). 

 Michelii,lJ',Jy.,M.(i/H. 



PHYTOLACCA. 



Hardy, greenhouse or stove herbs, shrubs, or trees 

 (ord. Phytolaccaceai), whose flowers are followed 

 by black berries, often in bunches. Only a few are 

 in cultivation, and the undernamed are among the 

 best of these. Propagated by seeds or division. 

 Common soil. 



Principal Species : 



acinosa, 2' to 5', sum., 



hdy., wh.; regarded by 



some authorities as a 



var. of decandra. 

 decandra, 3' to 10', sum., 



hdy. per., wh., roots 



poisonous. Virginian 



Poke-weed, Pigeon 



Berry. 

 - albo - variegata, Ivs. 



variegated. 



PHYTOPHTHORA. 



A genus of microscopic parasitic Fungi, small in 

 number of species, but possessing an enormous 

 power for mischief. The two species best known 

 are infestans and Fagi. Infestans, once placed in 

 the closely allied genus Peronospora, is known as 

 the cause of the Potato murrain, but it also attacks 

 the Tomato, as well as the Bitter Sweet (Solanum 

 Dulcamara) and Schizanthus. Although its 

 activity is generally confined to the members of 

 the order Solanacea?, it occasionally grows upon 

 members of Scrophularinerc. Fagi (syn. omnivora) 

 causes a troublesome disease, often attended with 



PltytarrJrim (sec Tillandsia). 



betonicoefolium of Vill., 



and scorzonerif olium) . 

 iiigrum, 6", Jy., red, bl. 

 orbiculare, 1', Je., bl. 

 pauciflorum, 4", Jy., bl. 

 Scheuchzeri, 1', My., bl. 

 Chanuelii, 9", My.. 



bl. 



Sieberi, 3" to 6", My., bl. 

 spicatum, 1' to 2^', Jy-> 



wh. or bl. 



dioica, 20' to 30', sum., 



grh. per., wh. (syns. 



arborea of gardens and 



Pircunia dioica). 

 icosandra, 3', sum., hlf- 



hdy. per., wh. (//. 



mexicana). 

 octaudra, 3 to 8', sum., 



hdy. per., wh. 



fatal consequences, in young Beech seedlings. It 

 attacks many cultivated Conifers, and occasionally 

 Maples and such low-growing plants as Semper- 

 vivums and Clarkias. 



The life cycle closely approaches that of the 

 Peronosporas, and the two genera are, in fact, only 

 separated by differences in the production of the 

 fruit (conidia), these conidia being borne several 

 in succession by one (branch) conidiophore, 

 instead of one conidium to a conidiophore, as in 

 Peronospora. 



It is only by repeated attentions that it can be 

 kept at bay. The production of winter or resting 

 spores has not yet been settled satisfactorily in 

 Phytophthora infestans. The following are the 

 best means of battling with the Potato disease : 



1. Protective earthing up to prevent direct in- 

 fection of the tubers. 



2. Spraying with Bordeaux Mixture at intervals 

 through the growing season to prevent infection of 

 the leaves and stems. 



3. Allowing 3' between the rows, to favour rapid 

 drying of the foliage, th'us removing one of the 

 chief aids to infection. 



4. The destruction by fire of all diseased haulms 

 and Potatoes. 



5. Dressings of gas lime in autumn from 12 Ib. 

 to 15 Ib. per square pole. 



6. Careful selection and frequent change of seed. 



7. The selection of disease-resisting varieties. 

 (See also POTATO.) 



When Fagi attacks young Beech trees it generally 

 makes its presence felt very early in the life of the 

 plant. The little plants commence to turn black 

 and die shortly after germination. The first 

 " rough " leaves may make their appearance before 

 the fateful spots show, but if the weather is damp 

 these spots increase in size with great rapidity. 

 Where the disease has made its appearance in a 

 seed bed the latter must be thoroughly disinfected 

 before being again used, and even then live years 

 at least should elapse before Beech seed is sown 

 upon the spot. All infected plants should be 

 burned. 



PHYTOPTUS. 



The genus Phytoptus has a sinister repute. 

 Several species injure cultivated plants. Ribis 

 causes the Big Bud in Black Currants ; Pyri attacks 

 the leaves of the Pear, and Avellana; the Hazel and 

 Filbert. These Gall Mites, as they are popularly 

 called, are of microscopic proportions. Their habit 

 of secreting themselves in the interior of the buds 

 renders them exceedingly difficult of detection. 

 Avellanao has been noticed in considerable numbers 

 in various fruit-growing districts, and it seems that 

 it is only the severe annual pruning of the trees 

 that has kept the pest under control. All such 

 prunings should be burnt, and, where occasional 

 swollen buds are seen, they also should be 

 picked off and burnt. The common wild Hazel is 

 as liable to attacks by the mites as the cultivated 

 trees, and there is not the hard annual pruning to 

 keep the pest in check, although it is probable that 

 the summer clippings would help materially that 

 is, if they were burnt at once. (For Ribis, see BLACK 

 CURRANTS and MITES.) Pyri, which causes galls 

 upon the leaves of Pears, behaves in a rather dif- 

 ferent manner. At first, and until just before the 

 fall of the leaves, the mites are ensconced inside the 

 yellow galls or blisters. In severe attacks these 

 galls become confluent, and the whole surface of 

 the leaf is involved. Just before the leaves fall 



