Ree. . July 10 

 Ans, Jan 28,1856 



Dyck June l6 t , 1855 



Yöur Wellborir 



Your comprehensive letter of May 3 p reeeived lately; T coul# 

 however, not pereeive, if my last shipment of illustrations has come 

 to you. I consider such Illustrations as entirely sufficient for the 

 work* which you are undertaking, , and, though it would with thia 

 type (lithographs, E.D. ) go much faster, than with copper engravings,, 



I cannot encourage you enoughr to execute your plans, to edlt a Syn- 

 opsis of the cacti therm and their geographica! distribution.. Both 

 would be raost useful; and it is stränge, how rieh the territory be- 

 tween the 30 th and 35th degrees latitude is in cylinder-shaped: Opun- 

 tias and in Mamillariae with furrowed warts.. 



I will have to answer first some questior* which you pose. 

 The 3 Opuntiae of Nuttall, which Poerster describes on page 468,. he 

 found in the Enumeratio of Pfeiffer, and he translates erroneously 

 the expression- subrotundu# with "almost round"*.- I posess your Op. 

 setispina, and it is quite healthy. - The species from Chihuahua,, 

 which I reeeived from you, is my 0p. albicans (may-be the ^ loevior).. 



II also have (grown from seed) your Op* phoeacantha — The spine bündle 

 of your Op.straminea is entirely like that of the 0p. tunlcata here;: 

 which, however is more white sralso, there raust be a large difference 

 between spine-bundles< f ormed in the homeland and those in our gardens fr 

 and thus I do not dare to decide about the identity of tunicata. . 



The Echlnoc. from Saltillo, which I posess in quantity, and about which 



you ask t ,I consider to be your Ech. setlsplnus- (wlthout k^ok-shapetf 



middle spines) - and the Op.elevatus ?' from CJuadelupe was the 0p o . 



imbrlcata Haw. - Pinally concerning the most ball-shaped Cereus from 



whienr 



the area of Mexico,) I considered te- be candlcans,, I had it searched in 



my garden, and the gardener, who has Charge of 



