APRIL, 1918. XANTHIUM AND SOLIDAGO MILLSPAUGH & SHERFF. 5 



The unique character of the foliage stamps this species as most 

 interesting. The leaves are remarkably like many of those met with 

 on Hibiscus militaris Cav., and undoubtedly give the species an 

 appearance in the field unlike that of any other North American 

 species. The burs have a body distinctly cylindrical, not ovoid, and 

 the beaks are curved. 



Xanthium crassifolium Millspaugh & Sherff sp. nov. PL IV, & Vfif. 4 & 8. 



Herba, veri similiter annua; caule inermi, superne setulis albis 

 (caulem inferiorem non vidimus) scabro. Folia alterna, crassa et non 

 membranacea, circumambitu subdeltoidea et tri-aut quinquelobata 

 (et foliis quarumdam Malvacearum, exempli gratia Sphaeralcea remota 

 (Greene) Fernald et Althaea officinalis L., simillima), basi triplinervia, 

 multis setulis albis adpressis scabra, numerosis punctis parvis resinae 

 punctata, petiolata, petiolis adjectis 5-17 cm. longa, petiolis laminis 

 subaequantibus; nullis areolis reticulatis manifestis supra aut infra. 

 Fructus singulatim aut 2-3 simul dispositi, anguste aut sublate cylin- 

 drico-fusiformi, badii, superne sensim duo rostra arcuata et hamosa 

 producti; exteriore facie 120-180 hamosis aculeis (3.5-5 mm. longis et 

 rostris subaequantibus) armati, pilosi et resina punctati ut aculei ad 

 basim et rostra infra; fructus corpore (rostris non adjectis) demum 

 1.7-1.8 cm. longo et 6-7.5 mm. crasso; rostris 4-6 mm. longis. Achenia 

 2 ; maiore circum 2 cm. longo et 6 mm. lato, 5-costato, transverse rugoso, 

 in suum basem orbiculatum et in rostri basem latum angustato abrupte. 



B. Mackensen 123, San Antonio, Texas, October 8 and November 

 15, 1911 (type in Herb. Field Museum, cat. no. 324122); Dr. ] . Gregg, 

 457, Sept. 20, sine loc. 1 (Herb. Missouri Botanical Garden, no. 



In certain characters, this species seems nearest Xanthium bubalo- 

 carpon Bush, which is described, however, as having the burs ovoid, 

 2.5-4 cm. long ("including the short beaks"), and 2-3 cm. thick ("in- 

 cluding the prickles"), the beaks 6-8 mm. long and the burs even much 

 exceeding in size those of X. speciosum Kearney, a species with burs 

 broader than those of X. crassifolium? 



In addition to the above four new species, represented in the 

 herbarium of this museum, we find still another among the specimens 

 belonging to the herbarium of the Missouri Botanical Garden: 



1 His numeration appears, however, to place this in Mexico. 



2 On going to press we have received a delayed consignment of plants from the 

 Missouri Botanical Garden. Among these is the type material of X. bubalocarpon 

 which we find strikingly distinct: its mammoth burs are not only much larger but 

 more closely and bristly echinate than those of X. crassifolium and the leaves are 

 larger and thinner. 



