1. An essay on the classification of Nemertes and Planariæ: preceded by some general considerations on the primary divisions of the animal kingdom Author(s): Girard, Charles, 1822-1895, author Publication: [New Haven?] : [publisher not identified], [1851] Subject(s): Invertebrates -- classificationAquatic Organisms -- classificationPlanarians -- classification
2. Essay on the classification of Nemertes and Planariæ: preceded by some general considerations on the primary divisions of the animal kingdom Author(s): Girard, Charles, 1822-1895, author Publication: [United States?] : [publisher not identified], [1852?] Subject(s): Invertebrates -- classificationAquatic Organisms -- classificationPlanarians -- classification
