40 FIELD MUSEUM or NATURAL HISTORY BOTANY, VOL. IV. 



likewise from "the neighbourhood of New York" ("on Long 



Island, near the sea-shore and marshes"). Rafinesque distinguished his 

 plant from X. echinatum, stating that X. echinatum had "oval fruits, 

 with aggregated, echinate, and hooked thorns." Without doubt, he had 

 in mind not the true X. echinatum Murr. but rather the plant later 

 described by Moretti as X. italicum. The fruits of his X. maculatum he 



described as "generally solitary half an inch long, nearly 



cylindrical obtuse, with the two beaks scarcely perceptible and bent in, 

 covered with short, thick and rough thorns, rather soft, and not uncinate." 

 From these characters (especially the ones which we have emphasized 

 with italics) as well as from the habitat given ("near the sea-shore 

 and marshes"), we feel certain that by X. maculatum Rafinesque meant 

 the plant which was really the true X. echinatum Murr. 



17. XANTHIUM ITALICUM Mor., Brugnatelli Giorn. fis., chim. Dec. II., 

 5: 326. 1822; Reichenbach Iconographia Botanica 4: 22, tab. 

 323. 1826. 



X. varians Greene, Pittonia 4: 59. 1899. 



X. glanduliferum Greene, loc. tit., 61. 



X. commune Britton, Manual 912. 1901. 



. Macounii Britton, he. tit. 913.* 



Caulis ramosus, scaber, lineis atro-purpureis saepe maculatus, 3-10 

 (-18 fide Moretti) dm. altus. Folia cordata aut late ovata, lobata, 

 dentata, utrinque setulis adpressis scabra, petiolis adjectis 0.8-3 dm. 

 longa, petiolis laminis subaequantibus aut excedentibus. Fructuum 

 (PI. VII, f. 17; PL IX, ff. 25-30) corpus nunc cylindricum, nunc oblong- 

 um, nunc ovoideum, sed saepius late oblongum, facie exteriore glandu- 

 loso-pubescens et aculeis armatum, 1.3-1.8 cm. longum, 6-8 mm. 

 crassum; rostris plerumque incurvatis et ad apicem hamosis, hispidis, 

 5-7 mm. longis; aculeis saepius numerosis et tenuibus (rariter vel sub- 

 remotis vel subcrassis), infra hispidis usque ad medium, supra glabris, 

 ad apicem hamosis, 3-7 mm. longis. 



DISTRIBUTION : Quebec, Connecticut and West Virginia to Saskatche- 

 wan, Washington, California and Oaxaca; southern Europe, Hawaiian 

 Islands, and probably elsewhere. 



1 We are not able to determine satisfactorily the identity of X. Cavanillesii 

 Schouw (Ind. Sem. Hort. Haun.: 14. 1849; Ann. Sc. Nat. s6r. Ill, 12: 357. 1849). 

 Cavanilles' type plate (Cav. Icon. 3: tab. 221. 1794) cited by Schouw, shows the 

 fruits glabrous, except, of course, as to beaks and prickles. If this plate be assumed 

 to be accurate, then the plant figured was undoubtedly X. chinense Mill. If, as seems 

 just as likely however, Cavanilles' plate was rather generalized and lacking in 

 detail, as are many of his other plates, then his plant specimen probably possessed 

 hispid-aculeate fruit and belonged to X. italicum. Cavanilles' description of the fruit 

 (loc. cit., p. n) is devoid of details as to pubescence: "Fructus ovato-oblongus, 

 pollicaris, estque drupa sicca, undique aculeis uncinatis tecta, apice bifida, cuius 

 mix bilocularis." Schouw's own description of the fruit ("Involucre fructigero 

 ovali, inter aculeos et ad basin rostrorum hispidissimo; aculeis tenuiter subulatis, 

 strictis, infer ioribus retrorsum porrectis; rostris tenuibus, strictis, apice un- 

 cinatis"), based, however, upon a specimen from Buenos Ayres, by Didrichsen, 

 might well pass for that of X. italicum. 



