THE RED HILL POOLS 

 S. B. Parish 



A]\IONG some interesting plants sent me this spring by ^Ir. 

 Ivan Johnston, an acute and enthusiastic botanical student 

 at Pomona College, were specimens of Pihdaria americana A. Br. 

 and of an Isoetes, which one naturally expected to be I. Orcuttii 

 A. A. Eaton, a little known species founded on plants collected 

 by Orcutt in winter pools on the mesa at San Diego. But on 

 comparison with Eaton's description it was found to be quite 

 distinct from that species. Mr. Maxon, to whom I sent speci- 

 mens, informs me that they match well with material in the U. S. 

 Xational Herbarium also collected by Orcutt in the San Diego 

 pools, and which Mr. A. A. Eaton had referred to /. niclanopoda 

 var. pallida Engelm., the type of which was collected long ago in 

 Texas by E. Hall. That, however, is described as having leaves 

 20 cm. long, while those of Mr. Johnston's plants are very slen- 

 der and but 3-5 cm. long. But for the present it may bear that 

 name. It is now first reported from the state. 



Mr. Johnston found these plants growing in winter pools at 

 a place near Upland, locally known as Red Hill. By his kindness 

 I was enabled to visit the place on the fourth of Alay in the 

 present year. There are four or five of these pools, none of 

 them more than a few yards wide in any part, and in depth less 

 than two feet below the surface of the red clay mesa in which 

 they are situated. At the time of my visit all the water had 

 evaporated, but the black loamy muck which forms the bottoms 

 of the pools was still moist. Both Isoetes and Pilularia had nearly 

 disappeared, so that by diligent search only a few withering 

 plants could be found. But the other vegetation of the pools 

 amply rewarded our visit. In all of them there was an abundant 

 growth of Psilocarphiis glohiferus Nutt. and Navarrctia pros- 

 trata Greene, and in two of them patches of CalUtriche longi- 

 pedunculata Morong. the type of which was also collected by 

 Orcutt in pools of this kind on the San Diego mesas. The slender 

 stems creep on the surface of the mud bottoms, forming a close 

 carpet, and are submerged when the pools are full. They were 

 now beginning to wither, and were without flowers, but the black 

 fruits were abundant. These are buried in the mud, a character 

 not noted by Morong, and which classes this species with C. 

 sepidta Wats and C. NnttaUii Torr. So far as I am aware the 

 present species is known only from the type station, but a CalU- 

 triche collected by Hasse in pools near Santa Monica is probably 

 the same. 



Over the dried pools waved the slender panicles of a Des- 

 champsia. I do not forgive myself for neglecting to collect speci- 



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