ER 
they 
that ZRRrERX are present on this form, .which seems to come close to 
cronata, unusually large. May-be it it approaches muricata „It will 
further be necessary to check the size of the veil (velum,E.D.). 
Other than the absence of stomata I have not found sure andmea- 
ningeful phenomenon for the examination of I. echinospora and ambisua, 
but the existence and absence of the stomata as a coincidence of geo- 
geraphical distribution is truly strange and justifies the differnti- 
ation.The size of the velum, andthe lesser broadening of the leaves 
toward the base of the americans may mean something, 1 believe, but 
nothing decisive. The canadian ambig resembles e.g. the europaeanı »*' 
echinospora_ in appearance to a fault, 
6. I.Boottii mihi or better I. muricata v. Boottii has the long- 
spined macrospores of I. ambigua. The length 3/4 and more covering; 
the velum as in I. muricata differs from both through the more stoma- 
ta which reach down to over the middle of tha leaf. Only one locality 
M 
"in a shallow pond near Osborn. 
7. I. muricata Woburn brooks and Abbe jona River; is not without 
stomata as I had written in my last letter,but has a few toward the tip 
of the leaves, no vascular bundles,, and a long one of the sporaneium 
with an almost coverinz velunm, Sporangium sclerenchyma cells ( as with 
I. ambigua amd Boottii)}) shorter and less regular indentations ( B, uses 
! 
"Löcher" = holes, E.D.) as with ambiesua and Boottii. The largest speci- 
mens from Woburn Brook, which I received recehtly directly from :BOOTT,, 
remind in habitat very much of Engelmanni of the same area..On these 
largest specimens I found the velum to be shorter, covering onlyY$. 
A specimen received from you in 1865 of unknom locality (from the area 
of Uxbridge ?), reported by Robbins as No. 9,.shows macrospores, which 
approach definitely those of I.riparia and Engelmanni , as this species 
seems generally (with exception of the lone velum) to be a connection 
of ambirma and riparia 
7 8 9 10 MIıSSOURI 
| | BOTANICAL 
(eloJe)/glelaimc-ti-Iai-Te GARDEN 
