256 THE CACTACEAE. 



dull purple around and especially below the areoles; leaves subtending the minute areoles, i to 



2 mm. long, caducous; areoles circular, bearing tawny or white wool when young; glochids short, 

 yellowish; spines numerous, very unequal, scarcely pungent, white to straw-colored or brownish, 



3 or 4 of lower ones almost hair-like, reflexed or appressed to joints, 3 or 4 of uppermost erect or 

 ascending, flattened, 2 to 3.5 cm. long; flowers not known; immature fruit glabrous at first, dull 

 green, becoming reddish purple especially about the areoles, 3 cm. long, bearing long white bristly 

 spines, especially from upper areoles, deeply umbilicate. 



Collected by W. B. Alexander in the barranca of the Tunuyan River near Tunuyan, 

 Mendoza, Argentina, March 22 and 23, 1921. 



This species is perhaps nearest Opuntia darwinii. We are under great obligation to 

 W. B. Alexander for sending us very fine living plants by Alexander Wetmore, who brought 

 them to us directly from Argentina. Mr. Wetmore was with Mr. Alexander when the 

 plant was collected and he has given us a word picture of the plant; we take pleasure in 

 naming the species for him, not only in recognition of this service but also for obtaining 

 other valuable specimens of cacti. 



Figure 234 is from a photograph of the type plant, one-half natural size. 



On page 95, vol. i, under Opuntia corrugata, insert: Tephrocactus rectrospinus (Index 

 Kewensis Suppl. i: 421) is a misspelling for T. rectrospinosus Lemaire. 



Also insert: Illustrations: Mollers Deutsche Gart. Zeit. 25: 476. f. 9, No. 11; 488. f. 

 22, No. 8. 



On page 95, vol. i, under Opuntia ovata, add: 



Opuntia pusilla Salm-Dyck (Observ. Bot. 3: 10. 1822. Not Haworth, 1812) was 

 referred by Schumann to 0. corrugata. We have seen a photograph of Haworth 's specimen 

 (bearing the date November 8, 1824) which seems to answer to Salm-Dyck's plant which 

 we would refer here. 



On page 96, vol. i, under Opuntia sphaerica, add the synonym: Opuntia ovata leonina 

 Schelle, Handb. Kakteenk. 46. 1907. 



Also add to illustrations: Deutsche Gart. Zeit. 7: 313, as Opttntia leonina; Schelle, 

 Handb. Kakteenk. 46. f. 8, as 0. grata leonina. 



On page 97, vol. i, under Opuntia pentlandii, add the synonym: Cactus bolivianus 

 Lemare, Cactees 88. 1868. 



Also add to illustrations: Watson, Cact. Cult. ed. 3. 106. f. 54; Deutsche Gart. Zeit. 7: 

 312; Schelle, Handb. Kakteenk. 58. f. 16, as Opuntia boliviana; Mollers Deutsche Gart. 

 Zeit. 25: 476. f. 9, No. 14. 



On page 99, vol. i, insert: 

 76a. Opuntia alexanderi sp. nov. 



Low, depressed, forming a small clump ; joints readily detached, grayish green, ^strongly tubercled, 

 globose, 2 to 3 cm. in diameter, nearly hidden by the numerous spines; areoles small, close together, 

 circular; spines 4 to 12, up to 4 cm. long, flexible, white below, dark above or with black tips, 

 scurfy-pubescent even in age; flowers not known; fruit red, dry, obovoid, 2 cm. long, lower areoles 

 not spiny, but upper ones bearing 2 to 8 long, white, erect, weak spines overtopping the fruit; 

 umbilicus of fruit depressed; seeds wliite, 5 to 6 mm. broad. 



Collected by W. B. Alexander, between Chilecito and Fanatina, province of La Rioja, 

 Argentina, February 19, 1921. Mr. Alexander studied this species in the field but could 

 not identify it and sent it to us for study. It belongs to the subgenus Tephrocactus, but is 

 not near any of the known species. We take great pleasure in naming it for Mr. Alexander, 

 who has extensively studied the cacti in Argentina. 



On page 100, vol. i, under Pumilae, add to distribution: Venezuela. 

 On page 100, vol. i, under Opuntia prtmila, insert: Illustration: Mollers Deutsche 

 Gart. Zeit. 25: 476. f. 9, No. 5. 



