regulation, and conservation of our Nation's water resources. The NAWQA Program, therefore, depends on advice and information from other agencies-Federal, State, interstate, Tribal, and local-as well as nongovernment organizations, industry, academia, and other stakeholder groups. Your assistance and suggestions are greatly appreciated.

Spatial distribution and abundance of Batrachospermum boryanum gametophytes within a headwater stream in Rhode Island, USA varied considerably over a period of two years due to significant changes in dominant substrata. However, periodicity of these plants was similar each year. Juvenile gametophytes were produced by the aseasonal annual 'chantransia' stage most abundantly in September and October. Macroscopic gametophytes appeared in November and attained a peak in development during late winter and spring, correlating with relative light penetration through the surrounding tree canopy. The ratio of female to male plants increased from 1: 1 in January to 4: 1 at the end of the growing season in June during both years. Spermatangia production was continuous throughout the growth period, averaging 26 000 mm -2; mean carpogonial density was 60 mm-2. Approximately 500 spermatia were released for each carpogonium present and the mean proportion of fertilized carpogonia was 22 % . Carposporophytes typically became detached and acted as dispersal agents, settling at 0.075 cm s-'. Current velocities in the stream varied from 10 to 50 cm s-and were calculated to carry the carposporophytes 5-35 m downstream. Monospores released by 'chantransia' upright filaments also added to population spread.

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Fifty-one stream segments were sampled in northwestern Newfoundland, central Labrador, and west-central Quebec during June and July 1987. There was a great range in stream size, current velocity, pH, and ion content. The eastern boreal forest was found to be one of the most diverse regions in North America for stream macroalgae, having a flora of 67 species. The major divisions in terms of species numbers were the Chlorophyta (43%), Cyanophyta (21%), Chrysophyta (19%), and Rhodophyta (16%). Mats were the most widespread form (51% of the species), followed by filaments (27%), colonies (13%), tissues (5%), and palmelloid forms (3%). Species number was positively correlated with water temperature and total cover and negatively correlated with pH. The most widespread species was Batrachospermum moniliforme, which occurred in 31% of the stream segments examined. Distribution was patchy, with total cover varying from < 1 to ca. 60% of the stream bottom. Species numbers per segment ranged from 1 to 11. The most closely associated species were Microspora pachyderma, Mougeotia sp., and Batrachospermum keratophytum. The known distribution range of the rare rhodophyte Boldia erythrosiphon was extended north by ca. 1000 km.

The Wood River watershed, a small well-defined drainage basin in Rhode Island was monitored seasonally for all macrophytic vegetation and various physical variables. Twenty-four segments, 20 m in length were sampled. Mean stream depth, width and current velocity increased by 3 to 8 fold from lst-to 4th-order segments. Light penetration was positively correlated with the above variables (p < 0.05) and increased by 11 fold from the headwaters to the mouth during September when the riparian canopy was maximum. 74 subgeneric taxa of macrophytes were collected in the Wood River basin, 36% algae, 13% bryophytes, 4% vascular cryptograms and 45% angiosperms. The highest diversity occurred in the 4th-order segments throughout the year. Species numbers were positively correlated with depth, width and light penetration (p < 0.05). Vascular plants dominated all orders, but their proportion doubled from lst-to 4th-order streams. Macrophyte cover was twice as high in the 4th-order segments in June and September as in the other orders. Macrophyte abundance was positively correlated to light penetration and negatively correlated to the ratio of nonvascular: vascular plants (p < 0.05). Two distinct clusters were found for the predominant species. The first cluster contained mostly large angiosperms, which were rooted in sediments, while the second cluster was composed of small epilithic algae and bryophytes. The moss, Fontinalis antipyretica, was the most frequent species, occurring in 51% of the samples and in all 4 orders throughout the year.