AN ENCYCLOPEDIA OF HORTICULTURE. 



167 



Hymenophyllum continued. 



H. scabrum (rough), sti. 2in. to 4in. long, wiry, ciliated, fronds 

 6in. to 15in. long, 2in. to 5in. broad, ovate-acuminate, tripin- 

 natifld ; lower pinnae 2in. to 3in. long, oblong-rhomboidal, acumi- 

 nate, divided nearly to the rachis. sori six to twenty to a pinna, 

 terminal on the lateral segments on both sides. New Zealand, 

 1859. Greenhouse. 



H. scriceum (silky), sti. 2in. to 4in. long, wiry, fronds pendent, 

 6in. to 24in. long, 2in. to 3in. broad, elongate-oblong, obtuse or 

 acuminate, simply pinnatifid ; pinnae lin. to 2in. long, numerous, 

 opposite, very variable in division, sori numerous to a pinna, 

 small, terminal on the apex of the pinn* and lateral segments. 

 Tropical America, 1859. 



H. tunbridgensc (Tunbridge).* sti. iin. to IJin. long, fronds 

 oblong-lanceolate, lin. to Sin. long, iin. to lin. broad, pinnate 

 throughout ; pinnae distichous, flabellato-pinnatifid ; lobes linear, 

 one to three lines long, spinulose, serrated, as is also the com- 

 pound involucre. Temperate regions (Britain). Hardy. See Fig. 257. 

 H. unilaterale (one-sided) This differs from H. tunbridgense in 

 the more ovoid and turgid involucre, in the darker green and more 

 rigid fronds, with the pinnae pinnatifid on the upper side chiefly. 

 Britain. See Fig. 258. Hardy. SYN. H. Wilsoni 

 H. Wilsoni (Wilson's). A synonym of H. unilaterale. 



HYMENOFTERA. A large and most important 

 order of insects, distinguished by the possession of four 

 membranous naked wings, supported by a network of 

 nerTares, and of a mouth furnished with jaws for biting. 

 They undergo a complete metamorphosis, their larvae being 

 usually like maggots, without feet, but with a distinct 

 head; their pupae are inclosed in a cocoon, and are 

 helpless, but the limbs lie free from the body, not adherent 

 to it, as in the Lepidoptera. The insects are seldom 

 of large size, but they are very numerous, and of very 

 varied habits. The more important groups to horticul- 

 turists are the following : 1. Sawflies, or Tenthredinidce. 

 In these, the female has a saw to bore a secure place 

 for depositing the eggs in leaves or branches. The 

 larvae feed on plants, and have six horny legs, and often 

 several fleshy legs, or prolegs, behind, so that they often 

 resemble larvae of moths. In the perfect insects, the 

 abdomen and the thorax are closely joined, without any 

 distinct stalk between them. Some of them make true 

 galls on leaves and twigs of Willows. 2. In this class 

 the females possess an ovipositor, and the abdomen is 

 fixed to the thorax by a distinct stalk. The larvae are foot- 

 less, and, except in one group, are parasitic in or on 

 other insects: hence they are frequently beneficial, In 

 this section are included the very abundant groups of the 

 Ichneumons and the Chalcides, both parasitic, and the 

 Gall-flies (Cynipidce), which are, in part, makers of true 

 galls on Oaks, Roses, &c., and in part parasites. 3. The 

 Sting-bearers (or Aculeate Hymenoptera). In these, the 

 females usually possess a sting connected with a poison- 

 gland, which they use as a weapon of defence. The an- 

 tennae are simple, and are formed of thirteen joints in 

 the males, and of twelve in the females. The larvae 

 are footless, and are usually supplied with food brought 

 by the perfect insects. The habits of the members of 

 this section are extremely various. Some are solitary, 

 and dig or build cells for the reception of their eggs, 

 which they surround with food for the larvae either 

 honey or pollen, or small insects, stung, so as to remain 

 helpless, though alive, till eaten by the larvae. Among 

 these are the Solitary Wasps and Solitary Bees. Others 

 live in societies (Honey Bees, Humble Bees, Wasps, and 

 Ants), often very numerous, and with a very complex 

 organisation. Often, in a community, there are perfect 

 males, perfect females, and undeveloped females or 

 workers, also called neuters. The workers do the work 

 of the rest, and some may even be modified specially as 

 soldiers, to fight in defence of the community. The 

 Bees are of special importance to many plants, because 

 of the great part they play in securing the fertilisation 

 of flowers, and thereby insuring the production of the 

 seed. See Galls, Honey Bee, Humble Bee, Ichneu- 

 mon Flies, and Sawflies. 



HYMENOSTACHYS. Included under Tricho- 

 manes (which see). 



HYOFHORBB (from hys, hyos, a hog, and phorbe, 

 food ; probably on account of the fruits being eaten by 

 pigs). OBD. Palmce. A genus of three species of orna- 

 mental, middle-sized stove palms, natives of the Mascarene 

 Islands. Flowers white, dioecious, produced in spikes. 

 Berries one-seeded, olive-like. Leaves terminal, pinnate. 

 Trunk unarmed. For culture, see Areca. 

 H. amaricanlis (bitter-stemmed).* I. pinnate, erect when young, 

 ultimately spreading from 4ft. to 6ft. in length ; pinnae stout, 

 broad, closely set together, about 2in. broad, acuminated. Trunk 

 and petioles very stout, deep maroon, glaucous, with an orange 

 line extending along the outer edges of the midrib. Mauritius, 

 1866. SViN. Areca speciosa. (I. H. 462, 3.) 

 H. Commersoniana (Commerson's). A synonym of Chrysalido- 



carpus lutescens. 

 H. Indica (Indian). A synonym of Chrysalidocarpus lutescem. 



FIG. 259. HYOPHORBE VERSCHAFFELTII. 



H. Verschaffeltli (Verschaffelt's).* I. pinnate, 4ft. to 6ft. long, 

 nearly erect, gracefully arching at the top; pinnoe linear-lanceolate, 

 acuminate, lift, to 2ft. long, lin. broad ; midribs white. Sheath 

 of the leaves forming a triangular columnar stem. Rodriquez. 

 A splendid species. See Fig. 259. (G. C. 1870, 418.) 



HYOSCYAMUS (from Hyos Kyamos (Hog's Bean), the 

 ancient Greek name used by Hippocrates). Henbane. 

 OBD. Solanacece. A genus comprising about nine species 

 of biennial or perennial erect herbs, inhabiting warm and 

 temperate Europe, Africa, and Asia. Corolla obliquely 

 campanulate or shortly funnel-shaped, five-lobed. Cap- 

 sule inclosed in the enlarged calyx, bursting when ripe 

 round a circular raised ring, immediately below the 

 hardened top. The species are of no particular horti- 

 cultural value, and the only one worth including, chiefly 

 for its medicinal properties, is H. niger. 



H. nlger (black), ft. very shortly stalked ; corolla pale dingy 



yellow, with purplish veins. Summer. I. rather large, sessile ; 



the upper ones stem-clasping, ovate, and regularly pinnatifid. 



h 1ft to 2ft. Europe (Britain), North Africa, North and West 



Asia, India. (B. M. PI. 194.) 



HYOSPATHE (from hys, hyos, a hog, and spathe ; 

 it is known in Brazil as Hog's Palm). OBD. Palmce. 

 A genus comprising three species of reed-like, unarmed, 

 stove palms, natives of Brazil. Flowers green, minute ; 



