cu MIDLAND NATURALIST. 
Resting Spores of Cosmarium bioculatum, Breb. 
]. A. NIEUWLAND. 
The material that is the subject for the present article 
was collected between May 1 and 14, 1907, on the University 
grounds in a small rill along the branch of the Michigan Central 
Railroad, between Niles, Michigan and South Bend, Indiana. 
The locality is rich in more or less uncommon algal material and 
the larger portion of the valuable specimens collected in the last 
few years for the department of Botany, in the line of fresh water 
algae, was obtained from the immediate vicinity, that is within 
a radius of a half mile. Until very lately the surface water of the 
surrounding higher land collected in small pools along the railroad, 
and the rill from which this material was obtained ,had its origin 
in an old barrelthat had formerly enclosed a spring. Its water flows 
along the tracks of the road into the St. Joseph River. Drainage 
systems have lately been put in and usefulness of the locality in 
the production of algal material is very much impaired. From 
July to November the streams and pools were completely dried 
up except after excessive rains.and even then they were dried 
up in a few days. The small stream was sluggish in its flow at 
intervals thus affording places for the lodgement of the plankton 
in the weeds and grass. The plankton was so abundant that it 
could be collected by the gallon. About the 15th of May the 
desmid material contained mostly Cosmarium bioculatum, Breb., 
Staurastrum rugulosum, Breb., Staurastrum polymorphum, Breb. 
Cosmarium botrytis, Menegh.,and Spirogyra tenuissima(Hass)Kutz., 
with lateral conjugation only, Zygnema insigne, (Hass.) Kutz., 
in fruit, various forms of diatoms, Vaucheria sessilis, (Vauch.) DC., 
Vaucheria geminata,  (Vauch.) DC, Draparnaldia glomerata 
(Vauch.) DC., Palmella hvalina, Breb., and Chaetophora elegans, 
Ag., also several forms of unicellular Myxophyceae. The desmid 
material was replaced by Mougeotia scalaris, Hass. so abundantly 
in the state of sexual reproduction that we considered it the best 
material we have ever found in that stage. The following algae 
were also present in the desmid material and all were 
abundant at different times between the beginning and the end 
of May: Cosmarium intermedium, a very small form of Penium 
margaritaceum, Breb. several species ot monoecious and dioecious 
