114 



The Canadian Field-Naturalist. 



[Vol. XXXV. 



That bright green hair-like growth so 

 eommon in ditclies and ponds is usual- 

 ly made up of one or more members 

 of t^iis family. Time will enlarge this 

 group greatly in Okanagan. Specific 

 identification is possible only when 

 filaments are in a fruiting condition 

 and zygospores present, an occurrence 

 not of great frequency. As yet I have 

 had no success with artificial cultures. 



Family Desmidiaceae. This family 

 is not represented in this list as the 

 writer has no literature on the subject. 

 The extreme difficulty in the study 

 of Desmids and the comparative scar- 

 city of good literature renders it a 

 subject for separate study. The Des- 

 mids are none the less of extreme beau- 

 ty and gz-eat interest, especially in 

 the apparent connection between the 

 richness of t^e Desmid flora and the 

 older Geological formations. In fu- 

 ture, however, I shall be in a position 

 to as.sign the Desmids to their respec- 

 tive genera. 



Division 3. Stephanokontae. 

 Order 1. Oedogoniales. 

 .57. Ocdogonhim .spec, sterile filaments 

 only have been collected. Specific 

 identification is impossible except 

 when in a fruiting condition, and even 

 then- it is a matter of difficultv. 



Division 4. Heterokontae. 



Order 1. Heterococcales. 



Family Chlorosaccaceae. 



58. Stipitococcus urceolafus, West, epi- 



phytic on RhicorJoiuKni hieroglyphi- 

 cum. 



Family Botryococcaceae. 



59. Botryocornis Braunii, Kutz., very 



common in plankton at all seasons. 



Order 2. TlKTRROTRIfHALES. 



Family Tribonemaceae. 



()(). Tribonema bombijciiium (Ag) Derb & 

 Sol, common in ditches. 



61. T. bombijcitnim forma minor (Wille) 

 West, as above. 



Order 3. Heterosiphonales. 

 Family Botrydiaceae. 



62. Botrydium (jroiiKlatum, Ehrenb. (L) 



Grev., uncommon and very interest- 

 ing; found on the drying up mud of 

 a small lake. May. Growing on flumes 

 (at the junction of the boards, where 

 slow leakage occurs) to a size much 

 larger than usuallv recorded. 



CLASS PHAEOPHYOEAE. 



Order Syngeneticae. 

 Family Chrysomonadlinaceae. 



63. Synura uvella, Ehrenb., slough plank- 

 ton. 



64. TJroghnn volvox, Ehrenb., as above. 



Family Dinobryaceae. 



65. Dinohryov cylindricum Imhof., slough 



plankton. 



The ^system of classification used in 

 this list is that of Prof. G. S. West 

 in his work on Algae, Vol. 1, Cam- 

 bridge Botanical Handbooks, 1916. It 

 is, I think, tjie most modern classifi- 

 cation and in harmony with the latest 

 biological experience. 



The species enumerated in this list 

 are all positive identifications and are 

 for the most part the result of the 

 independent observations of Mr. F. L. 

 McKeever, F.R.M.S., and myself. A 

 great many of the collections were 

 made by us jointly, but the micro- 

 scopical investigations were carried 

 on separately in our own homes. 

 Doubtful species and errors are there- 

 fore absolutely eliminated. 



The list is as yet woefully incom- 

 plete, but T hope in the course of a few 

 vears to lengthen it to a great extent. 



