8 DR. ОТТО STAPF ON HALLIERACANTHA, 
also in regard to pollen-structure) will probably give the key to the phylo- 
genetic position of Hallieracantha. 
Before proceeding to the purely descriptive part of the paper, I would 
indicate the characters which distinguish /Hallieracantha and Ptyssiglottis. 
They concern mainly the inflorescence, the corolla, and the pollen. The 
inflorescences of НаШетасап а, are axillary or rarely pseudoterminal, loose 
or much contracted, and made up of dichotomously arranged dichasia. Those 
of Ptyssiglottis are terminal and represent few-flowered, more or less one- 
sided racemes. The corolla of Hallieracantha consists of a tube which is 
somewhat obliquely widened in the upper part and a typically bilabiate limb, 
in most species three to five times shorter than the tube. The upper lip is 
very shortly, the lower more deeply lobed, and the latter has two conspicuous 
vaulted ridges on the palate. On the other hand, the corolla of Ptyssiglottis 
is obliquely companulate, with a very short cylindrical tube at the base ; it 
has a wide mouth, and the lobes of the limb are much less unequal than in 
Hallieracantha, nor is there a distinct vaulted palate. In Hallieracantha the 
stamens spring from the middle of the tube, in Ptyssiglottis the insertion 
is considerably lower down. The pollen of Hallieracantha is throughout 
ellipsoid, in Ptyssiglottis globose. I may add that the leaves of Ptyssiglottis are 
thin and of a texture such as does not occur in Hallieracantha. The 
characters given here for Hallieracantha are common to all its species, and 
it 1s their constant correlation that marks the genus as distinct from 
Ptyssiglottis. 
HALLIERACANTHA, Stapf. 
Calyæ fere ad basin 5-partitus (rarissime 9-dentatus), segmentis zequalibus 
linearibus vel subulatis. Corolla bilabiata ; tubus limbo plerumque 8—5р1о, 
rarius tantum 2plo longior, infra medium magis minusve cylindricus, superne 
sensim ampliatus; labium superum erectum, emarginatum vel breviter 
2-lobum ; labium inferum superum eequans vel subsequans, 3-lobum, lobis 
sub:equilongis, lateralibus oblongis vel ovatis, intermedio latiore in alabastro 
extimo ; palatum 2-plicato-fornieatum. Stamina 2, medio tubo vel paulo 
supra orta, e corollæ tubo vix exserta; filamenta glabra; anther 2-loculares 
thecis zequalibus vel rarius inzequalibus oblongis muticis subparallelis dorso 
connectivo angusto eadem altitudine (vel una quam altera paulo altius) 
adnatis subcontiguis. Pollen ellipsoideus, poris 3 zequatorialibus plieze tenuis- 
sime polos haud attingenti impositis plerumque plicis aecessoriis utrinque 
singulis additis, exinio tenuissime punctato vel raro levi ; staminodia nulla. 
Discus annularis vel breviter tubulosus, ovarium arcte cingens. Ovarium 
glabrum vel parce papilloso-pilosulum ; loculi 2-ovulati ; stylus filiformis, 
glaber; stigma punctiforme vel paulo dilatatum. Capsula clavata oblonga, 
acuminata vel apiculata, ad fere medium solida, coriaceo-indurata. Semina 
lenticularia, tenuiter scrobiculata.—Herbæ erecti vel procumbentes, simplices 
