488 Mr. J. Miers on the Tribe Colletiese. 



has not only a distinct form of calyx, but it is quite dissimilar in 

 the structure of its fruit, which is enclosed in the entire un- 

 changed persistent calyx, and which consists of an evalvate in- 

 dehiscent membranaceous pericarp that bursts by laceration, 

 only to allow of the escape of the seeds. The name of the genus 

 was derived from the vernacular appellation of the typical species, 

 Trevo or Trebu. Its character is thus defined : 



TREVOA, nob. Calyx petaloideus, tubulosus, tubo imo inflate, 

 medio ssepe constricto, fauce paulo ampliore, intus prsesertim 

 versus basin villosissimo, pilis albidis retrorsis, limbi laciniis 

 4 vel 5, triangularibus, erectiusculis, intus carina calloque 

 notatis, marcescens et persistens. Petala 4-5, rotundata, cu- 

 cullata, unguiculata, laciniis calycinis breviora, erecta. Stamina 

 4-5, petalis inclusa, et cum eorum unguibus inter lacinias in- 

 serta; filamenta brevia, pilosa, imo complanata, subulata, 

 apice repente inflexa; anthera rotundatse, eis Retamilia similes. 

 Discus parvus, carnosus, ovario 3-plo latior, subconcavus, ad- 

 natus. Ovarium e medio disci superum, conico-oblongum, 

 2 3-sulcatum, hirsutissimum, 2-3-loculare. Stylus erectus, 

 3 4-gonus, angulis ciliatis, imo validiusculus et hirsutissimus. 

 Stigma 2-3-loburn, lobis obtusis arete adpressis, albidum. 

 Fructus drupaceus, ovatus, subcompressus, calyce marcido imo 

 suffultus, endocarpio indehiscente nucamentaceo, 2-3-loculare, 

 vel abortu uniloculare. Semen in quoque loculo solitarium, 

 erectum, compresso-ovatum, nitidissimum, structura omnino 

 Colletia. 



Arbusculse Chilenses frondosa, ramosissimte, spinosa, trunci ligno 

 durOj ramis oppositis, ramulis infra spinas foliiferis et floriferis, 

 spinis oppositis; folia opposita, ovata, serrulata, 3-nervia, fere 

 glabra ; flores e ramulis junioribus enati, in axillis oppositis 

 solitarii, vel 2-3, fasciculati, hinc foliis carentibus scepe race- 

 mosij aut axillis approximatis quasi spicati. 



1. Trevoa trinervis, nob. Trav. ii. 529 ; T. trinervia, Hook. Bot. 

 Misc. i. 159 ; Retanilla trinervia, Hook, in parte, ibid. iii. 

 174 ; Colletia Trebu, Bert. ; Colla, Mem. Torin. 37. p. 53 ; 

 arbuscula sesquiorgyalis, ligno duro rubente, ramosa, ramulis 

 compressis, foliosis, spinosis, junioribus inermibus foliiferis et 

 floriferis sub spinis enatis ; spinis viridibus, decussatim oppo- 

 sitis, compresso-subulatis, calloso-pungentibus, patentissimis ; 

 foliis oppositis, ovalibus, mucronulatis, imo in petiolum cunea- 

 tis, crenulato-dentatis, 3-nervibus, nervis pellucidis subparal- 

 lelis, lateralibus versus marginern ramosis, et hinc in glandulas 

 marginales excurrentibus, reticulato - venosis, glabriusculis, 

 petiolo brevi, canaliculate, singulis e stipula fusca bifida ortis ; 

 floribus interdum quasi spicatis ; pedunculo brevissimo, piloso ; 



