This section is from the book "British Wild Flowers - In Their Natural Haunts Vol5-6", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
The habitat of this plant is lakes and streams and hedges. The habit is slightly arching. The stem has fine, numerous, long, white hairs, and is somewhat furrowed. The prickles are numerous, short, with a stout base. The leaves are 5-lobed, small. The leaflets are narrow, sharply toothed, with compound teeth towards the point. The panicle is rather broadly cylindrical, with many strong, turned-down, and sickle-like prickles and pricklets. The flowers are numerous, handsome, and starlike in sunshine. The stamens are numerous and long, exceeding the green styles. The plant resembles R. Lindebergii, differing in the weak, slightly-furrowed stem, narrow, thin leaflets with compound teeth above, and many broad compound panicles.