LXXXV. ASCLEPIADE-ffi (bROWN). 233 



study, but they may be conveniently divided into primary groups in accordance 

 with the character of the pollen, which it is always necessary to examine before any 

 generic identification of an unknown plant of this Order can be made. The pollen 

 is of 4 distinct types, as follows : — 1. Granular and loosely contained in the more or 

 less spathulate or bifid pollen-carriers, not attached to the latter ; this type 

 characterises the tribe Periplocece. 2. United into very minute waxy masses, 

 4 or 2 of which are sessile upon a very minute quadrate, pale-coloured pollen- 

 carrier; this type characterises the tribe Secamonece. 3. United into waxy masses, 

 which are opaque without a pellucid margin, usually not very minute, and are 

 attached in pairs by caudicles to the dark-coloured pollen-carriers ; to this type 

 belong the tribes Ct/nanchece with pendulous pollen-masses, and MarsdeniecB with 

 erect or horizontal pollen-masses. 4. United into waxy masses which are pellucid 

 on one margin or at the apex, and attached in pairs by caudicles to the pollen- 

 carriers; to this type the tribes CeropegiecB and StapeliecB belong. 



In the following descriptions, the dimensions of the dried flowers I have ex- 

 amined are always taken after having boiled them jn water and will thus often he 

 found to considerably exceed similar measurements made of them in a dried state, 

 thus more nearly approaching the dimensions of the living flowers.. Owing to their 

 fleshy nature, the coronal-lobes, when subjected to much pressure, often have their 

 original form quite altered if not totally destroyed ; this has led to much discrepancy 

 in various descriptions of the same plant. In preparing the following descriptions 

 I have therefore always selected flowers for examination (usually 3 or 4 from eacli 

 specimen when the material was sufficient,) that were saved from undue pressure by 

 their proximity to the stem or other thick parts, such flowers always giving a better 

 and more correct idea of the form of the coronal-lobes when alive than do flowei's 

 that have been badly pressed. In the measurements given, the length of the 

 coronal-lobes is always intended to include any horn or other appendages they may 

 have, unless otherwise expressed or wlien such appendages are horizontal or reflexed. 

 The term " conoid," applied to the apical part of the style in some of the following 

 descriptions, is used in the same sense as oricjinally employed by Schott to describe 

 the appendix of the spadix of many Aroids, where that organ is much elongated and 

 slightly tapers from or near the base to an obtuse apex. 



Tribe. I. Periploceee. — Filaments of the stamens free {see also Xysma- 

 lobium barbigerum). Anthers triangular or oblong, their connectives produced 

 beyond the cells into short terminal points {apiculate), or into small dilated, mem- 

 branous or somewhat fleshy appendages, connivent over the apex of the style and 

 frequently connate at their tips. Pollen-contents of each anther-cell of numerous 

 loose granules, each granule formed of 4^* pollen-grains united in tetrads. Pollen- 

 carriers spathulate, trumpet-shaped, or trowel-shaped, sometimes bipartite, horny, 

 furnished with an adhesive gland at their base, not attached to the follen-grains, 

 iut holding them loosely in their concave upper part. 

 Coronal-lobes none; flowers small, in dicliotomous or 



trichotomous cymes 8. Baseonema. 



Coronal-lobes very minute, entirely adnate to the 

 staminal-filaments, easily overlooked ; flowers very 

 small, crowded in small long-peduncled clusters . 1. Gymnol.ema. 

 Corona indistinct, annular, with 5 very short lobules 

 adnate to the base of the staminal-filaments; 

 flowers moderately large in long lax panicles . 4. Batesanthus. 



Coronal-lobes 5, distinct, entire, or 2-10-fid, entirely 

 free or only adnate just at their base to the 

 staminal-filaments, alternating with the corolla- 

 lobes. 



