278 PHANEROGAM I A. 



A genus (the floral characters of which have not before been indi- 

 cated), with nearly the foliage and venation of Frangula, and the 

 flowers of Colubrina; distinguished by the very strongly salient crest 

 of the inner face of the sepals, by the anther-cells pointed at their 

 base, and by the membrane that encloses the seeds. I doubt if this 

 membrane is truly an arillus ; but our materials are not sufficient for 

 the complete investigation of its nature. Although marked with 

 what seems like a rhaphe, it cannot be the testa or any proper inte- 

 gument of the seed, as Fenzl (in PI. Hugel.) took it to be, for it has 

 no connexion with the corneous seed-coat at the chalaza, but only at 

 the hilum. The chalazal end appears to be slightly open, as would 

 be the case with an arillus. The cocci of the Australian species (A. 

 excelsa), the flowers of which are still unknown, often fall away after 

 dehiscence, just as in A. zizyphoides, so as to leave the seeds attached 

 to the persistent cupulate base, and enclosed in their fragile arillus ? 

 Perhaps this membrane is a separable lining of the coccus. 



1. Alphitonia ziztphoides. (Tab. 22.) 



A. foliis oblongo-lanceolatis seu ovato-lanceolatis acuminatis glabratis 

 supra nitidis subtus albidis venulisque inter venas primarias rectius- 

 culas eximie reticulatis. 



Rhamnus zizyphoides, Soland. in Forst. Prodr. Ins. Austr. p. 90 (absq. char.) • 



Spreng. Syst. 1, p. 768 j DC. Prodr. 2, p. 27. 

 E. incana, Eoxb. j Spreng. Syst. Veg. Cur. Post. p. 86 ? fide spec. Hort. Calcutt. 

 Pomaderris zizyphoides, Hook. & Am. Bot. Beech. Voj. p. 61. 



Hab. Tongatabu. Samoan or Navigators' Islands. Ovolau, Feejee 

 Islands. (Tahiti, Barclay, &c.) 



" Tree 20 to 30 feet high, the trunk often a foot in diameter." 

 Young branchlets, petioles, the midrib of the leaves, and the inflores- 

 cence clothed with a minute, more or less deciduous, ferrugineous 

 tomentum. Leaves oblong -lanceolate or ovate-lanceolate, acuminate, 

 usually with a gradually tapering point, from 3 to 6 inches long, 

 entire, or obsoletely repand-serrulate, thin but coriaceous in texture, 

 soon glabrate both sides, the upper very smooth and shining, the 

 lower ivhitish or minutely canescent, with the straightish primary veins 



