THE CACTACEAE. 



1. Echinocereus delaetii Giirke, Monatsschr. Kakteenk. 19: 131. 1909. 



Cephalocereus delaetii Giirke, Monatsschr. Kakteenk. 19: 116. 1909. 

 Low, 1 to 2 dm. high, densely eespitose, completely hidden by the long, white, curled hairs ; 

 ribs indistinct; areoles closely set, bearing 15 or more white reflexed hairs 8 to 10 cm. long and a 

 few stiff reddish bristles; flowers appearing near top of plant; perianth-segments pink, oblanceo- 

 late, acute; stigma-lobes about 12; ovary covered with clusters of long, white, bristly spines; fruit 

 not seen. 



Type locality: Not cited. 



Distribution: Known only from Sierra de la Paila, north of Parras, Mexico. 



This is the most remarkable species in the genus ; in aspect it resembles small plants 

 of Cephalocereus senilis, and owing to this resemblance it was first described as a Cephalo- 

 cereus. Its flowers, however, are so different from those of that genus that as soon as 

 they were seen the plant was at once transferred to Echinocereus. 



The plant is now largely imported into Europe and can be obtained from many 

 dealers; it was named in honor of Frantz de Laet, a Belgian cactus dealer, who had imported 

 many plants from Mexico through Dr. C. A. Purpus and other collectors. 



Illustrations: Monatsschr. Kakteenk. 

 19: 119, as Cephalocereus delaetii; Monats- 

 schr. Kakteenk. 22: 73; Rev. Hort. Beige 

 40: after 184. 



Text-figure 1 is from a photograph of 

 the plant received from M. de Laet. 



2. Echinocereus scheeri (Salm-Dyck) Riimpler 



in Forster, Handb. Cact. ed. 2. 801. 1885. 



Cereus scheeri Salm-Dyck, Cact. Hort. Dyck. 

 1849. 190. 1850. 



Cespitose; stems procumbent, prostrate or 

 ascending, decidedly narrowed towards the tip, 

 10 to 22 cm. long, yellowish green; ribs 8 to 10, 

 rather low, not at all sinuate, somewhat spiraled ; 

 spines 7 to 12, acicular, white with brown or 

 blackish tips; flowers 12 cm. long, rose-red to 

 crimson, with an elongated tube; perianth- 

 segments oblanceolate, acute; fruit not known. 



Type locality: Near Chihuahua. 



Distribution: Chihuahua, Mexico. 



The species was named for Frederick 

 Scheer (1 792-1868), who described the cacti 

 for Seemann in the Botany of the Herald. 



Lemaire used this name as early as 1868 (Les Cactees 57), but did not formally transfer 

 or describe it, and it is not published or even mentioned by Lemaire in Manuel de 1' Amateur 

 de Cactus (1845) as stated in Bliihende Kakteen under plate 14. It seems to be a distinct 

 species, related to E. salm-dyckianus, but with differently colored flowers and shorter 

 spines. The variety E. scheeri nigrispinus was used by Scheer in Botany of the Herald 291 . 



The type of this species seems to have been lost ; it was collected by John Potts, a mining 

 engineer, at one time stationed in Chihuahua, Mexico. We know the species only from 

 description and illustrations. 



Echinocereus scheeri vars. major and minor (Monatsschr. Kakteenk. 15: 175. 1905) 

 and var. robnstior (Monatsschr. Kakteenk. 15: 161. 1905) are only garden forms. 



Illustrations: Curtis's Bot. Mag. 132: pi. 8096, as Cereus scheeri; Bliihende Kakteen 1: 

 pi. 14; Schumann, Gesamtb. Kakteen f. 48. 



Text-figure 2 is from a part of the second illustration above cited. 



