106 BOTANICAL GAZETTE [ AUGUST 
valley, either a form of S. canescens or a closely allied species. It 
comes into flower very early; this year I found the first on January 31. 
It is visited in February by honey bees, but not by native bees, which 
are not out so early. Nevertheless, by the end of February it has set 
numerous pods. ‘This would not call for particular comment but for 
the fact that by the middle of April, when the native bees are out, it 
proves to be a most attractive bee plant. That is to say, it is very 
attractive to bees (mostly Andrenidze), but can do quite well without 
them. Persons observing the flowers at different times of the year 
might thus reach very different conclusions. 
It is also true, with some of our flowers, that observations made in 
different seasons or localities, though at the same time of the year, 
would yield quite different results. For example, take the, cultivated 
plums in the Mesilla valley, the white flowers of which are very attrac- 
tive to bees, especially Andrenidz. On April g to 12, 1895, on the 
farm of the Agricultural Experiment Station, Miss J. E. Casad and the 
present writer took the following bees from flowers of plum: Afzs 
mellifica \.., Osmia prunorum Ckll., O. cerast CkIl., Nomada incerta 
Cresson, Sywhalonia lycit Ckll. (ined.), Podalirius affabilis Cresson, 
Anthidium sp. (escaped capture), Prosapis mesille Ckll., Agapostemon 
texanus Cresson, Halictus, 2 sp., Andrena sphecodina Csd. & CkIl., 4. 
jessice Ckll., A. prunorum Ckll., A. casad@e Ckll., A. nigerrima Casad. 
A. fracta Csd. & CkIl., A. electrica Csd. & Ckll. There were also taken 
or seen various other insects, including Danais archippus, Pyramels 
cardut, Colias eurytheme, Heliothis armigera, Peridroma saucia, Everge.’.s 
simulatalis Grote, among the lepidoptera; Sarcophaga incerta Walker, 
Alophora luctuosa Bigot (both det. Coquillett), among the diptera, 
etc. Now this year (1897) I was anxious to obtain further material 
of several of the above bees, and so watched the plum trees carefully. 
On March 24, in Mesilla, I caught one ¢ Andrena fracta; on April 4 
one Halictus amicus Ckll. (ined.); on April 15 I saw a Boméous; but the 
species of 1895 were for the most part totally absent! I visited the 
very same trees at the very same time, and still failed to find the bees. 
Had a stranger come here to collect, with the account of the 1895 
captures before him, surely he would have set me down a liar. It 
would have seemed incredible that the experience of one year should 
be so flatly contradicted by that of another. 
I have been interested this year in watching in Mesilla our native 
Sambucus mexicana. Miiller, writing of S. nigra, remarks on the absence 
; 
