Complex sentence: Notable palms in the consrvatory's collection include the Windmill Palm (Trachycarpus fortunei) donated by Hiram Chittenden Locks circa 1953 and the Sago Palm (Cycas revoluta) which was about 80 years old in 2009.
Split into simpler sentences: Notable palms in the consrvatory's collection include the Windmill Palm (Trachycarpus fortunei) donated by Hiram Chittenden Locks circa 1953. A featured Sago Palm (Cycas revoluta, not a true palm, but a member of the Cyadaceae) was about 80 years old in 2009.