... including Diagnosis of European Spongillidae by Prof. Franz Vejdovsky 

Hardcover 8vo, in brown buckram with gilt leather spine label. iv, [157]-279pp+ 7 plates labeled Plate V-XII (“inclusive”), 1887. Bound with 5 offprints extracted from “The Microscope” originally collected in seafoam green wrappers titled “Fresh Water Sponges” and containing: (1.) –What They Are Not. (2.) What They Are [June 1890, with plate] (3.) What They Are [July 1890, with plate] (4.) How to Find and Gather Them [Sept 1890] (5.) The Determination of Species [with diagram].

Inscribed twice “from Edward Potts” beneath the ownership signature of Mr. S. R. [Sherwood Raymond] Roberts on the front blank of the monograph and the first page of the offprints pamphlet. Roberts was a colleague of Potts and prominent member of the Academy of Natural Sciences of Philadelphia, known for his work in conchology and collection of Cypraeidae that rivaled Potts’ collection of fresh water sponges (both of which were ultimately donated to the Academy). In Near Fine condition; a rare and exciting collection of works.