26 



J. O HAQSTROM, CRITICAL RESEARCHES ON THE TOTAMOGETONS. 



P. Stlictns Phil. Florula atacamensis, 1860, 50. 



P. aulacophyUus Schumann in Fl. brasil. III. 3, 1894, 696. — Fig. 7, Å—B. 



This species also comes very near to P. filifonnis. As to style, stigma and 

 ripe fruit it may hardly be discerned from it. The way of branching, likewise, is 

 also the same: every sheath embraces but one branch. 



The low-grown form, being only 9 — 13 cm high, is to be considered as main- 

 form. It has comparatively short (3—6 cm) leaves and short sheaths. Leaves usu- 



Fir. 7. A Ii, P. slrieluå rnri... C 1>, V. stridits Pmi.. var. magellaniau Haqbth. A, Apas <>f a .stcm-leaf, ',", the bottoms 

 and walli ol ilnj lacnum visible. u, Transverse sectioD of a utem-leaf (middle part), «, vascnlar hundle of the midrib, f>, lateral 

 bandlcs, ' : ,°. />, apex of a stem-loaf of v. magell., ; , , buttonm and walla of the lat-unm visible. C, Tranaverae seetion of a stcm- 



lcaf, middle part, a, and b, as in B, shl, marginal baatbnndles, "j - 



ally a little över 1 min broad, of the same width up to the rounded apex, canali- 

 culate and obtusely keeled, 3-ncrved, the lateral nerves being a little more removed 

 from the margin than in P. filifonnis. Ligules truncate or snbretuse. A cross- 

 section of the leaf presents very seldom a faint aubepidermal strand which, again, 

 ahvays is to be fonnd in the variety described below. The peduncles are short, 

 2.5 4 ( — (i 7) cm, also the spikes that consist of 3—4 approximated verticils. 



Anatomy of atem: The Philippian apecimena of Ataoama exhibit tho following 

 peculiaritiee : ESpidennis of long narrow cHls, uiside atrengthened by an one-celled 

 paeudo-hypoderma along which appears a oircle of large-roomed lacun», evident lv 

 wider thanin P. filifonnis, whereon iollow 2 3 circlea of narrower lacunsa. Three 



