
34 Contributions from the Gray Herbarium 
he referred it to Lappula (L. stipitata (Greene) Druce, 1. ¢). 
Rather does it seem probable that the plant collected as a waif 
in England was, in fact, one of the annual species of Lappula 
although the fact that the determination was made by Dr. Thel- 
lung decidedly weakens this theory. It may be remarked that 
Lappula is strongly characterized by the position of the prickly- 
margined nutlets. These are erect on an elevated receptacle. 
They are sometimes armed on the back as well as on the margins” 
but the prickles are always hooked. The nutlets of Allocarya on 
the other hand are obliquely attached to a low-conical receptacle — 
and are never armed with hooked prickles. Allocarya is most 
closely related to Plagiobothrys and if Mr. Druce had referred his | 
plant to the latter genus some well-taken arguments for his action 
could be presented. These genera also, however, are nicely dis- 
tinct although in nutlet-character they approach each other 
closely. The attachment of the nutlets of Plagiobothrys is nearly 
or quite medial rather than basal or supra-basal and the leaves — 
are never opposite as are the lower ones of Allocarya. The fact 
that both genera contain numerous species none of which fail mn 
any degree to conform to the generic character in each case 18 the 
best argument to my mind as to the validity of these genera. 
Allocarya mexicana, spec. nov., ut videtur perennis; caulibus 
mediocriter crassis subdecumbentibus usque ad 1.5 dm. longis 
; ‘5 pili joribus 
abris vel parce pubescentibus cum nonnullis pilis longionby 
fs ' “ foliis linearibus obtush 
plerumque circa 2.5 em. longis (superioribus non reductis) VIX — 
laciniis cirea 
latis; calycis subadpresse villoso-hirsuti fructiferi I poem 
. longis plus minusve inaequalibus; pedicellis 7 : 
This species is closely related to A. linifolia (Lehm.) a ap 
South America from which it is nicely distinct, however, by BM | 
characters. The nutlets of the South American plant are O” 2° 
ovate, almost deltoid, only about 1 mm. long and irre pee 
rugose dorsally rather than finely reticulate-rugose 3% they ‘eh 
A. mexicana. A. linifolia is also more pubescent and gee 
appears to be more tufted with the stems not greatly elonga! = : 

