78 PROCEEDINGS OP THE AMERICAN ACADEMY 



of the somewhat gamophyllous calyx-limb from the fruit at the matu- 

 rity or at the dehiscence of the latter. It is by an oversight tliat the 

 limb of the calyx in Crusea is characterized as persistent in DC. Prodr. 

 iv. 5G7, and in Benth. & Hook. Gen. ii. 144. The oriirinal char- 

 acter in the Linnaea, v. 165, " Achojnia .... spermopodio persistenti 

 piano apice affixa, sub maturitati spoute desilientia, integro calycis 

 limbo turn seorsim deciduo," is explicit in this regard, and is correct. 

 By all the essential characters we must refer to Crusea two small- 

 flowered species of somewhat different habit, namely: — 



Crusea subulata.* Borreria subulata, DC. Prodr. iv. 543. Sper- 

 macoce subulata, Pavon ex DC. ; Ilerasl. Biol. Centr.-Am. Bot. ii. GO. 

 Besides the casting of the calyx-limb at dehiscence, the two carpels in 

 this species leave in the axis a conspicuous carpophore, of their own 

 length, narrow, and subulately bifid to near the middle, so that the 

 plant could belong neither to Spermacoce nor to Diodia, and the car- 

 pels dehisce by a chink down the whole length of the commissural face. 

 This species, not uncommon in Mexico, was collected by Wright in 

 Arizona; at least seeds were gathered by him from which plants were 

 raised in the Botanic Garden of Harvard University in the year 1852 ; 

 and recently it has been collected in the same district by Lemmon. 



Crusea allococca. Referring this to Crusea, I shall not add 

 unnecessarily to the synonymy by imposing this specific name. It is 

 Diodia tricocca, Torr. & Gray, Fl. ii. 30, and D. tetracocca, Hemsl. 

 I.e. 56, t. 40, f. 10-15, and the carpels vary from three to four, both in 

 Texan and in Mexican specimens, although the lesser number prevails 

 in Texas. The species varies greatly in the width of the leaves and 

 in pubescence ; both the fruits and the herbage are sometimes quite 

 smooth and glabrous, sometimes puberulent or hirsute, and in no. 1187 

 of Palmer's collection even hispid. The carpels are dorsally very con- 

 vex, ventrally flattened, and either closed or with the thin commissural 

 face more or less ruptured in dehiscence ; the carpophore weak, and 



lias been inadvertently written Mltracarprim by all succeeding botanists, except 

 Bentliam (in Bot. Voy. Sulph.) and myself, who endeavored to improve it into 

 Milracarpium. By referring to the original publication of Zuccarini's name and 

 cliaracter in Roem. & Scliult. Syst. Mant. iii. 210, it will be seen that the "Mitra- 

 carpum" and the ^'Mllracarpum scahrum " there cited are accusatives (as the form 

 of the word should sufficiently indicate) ; and the index to the volume accord- 

 ingly gives us "Mitracarpus scaler." No increase of the synonymy should come 

 from the remanding of the genus to its proper gender. 



» The "Cnisca sulmlata " in Ilemsley, Biol. Centr.-Am. Bot. 1. c. 57, is a slip of 

 the pen or a misprint of Cmsca subalaia, Uook. &. Am. Bot. Beech. Voy. 431. 



