A set of eleven plaster models mounted on wooden bases, each representing a stage in the development of the frog embryo. In contrast with similar Mueller-Ward models, which are primarily painted brown, models of this type are painted in bright, contrasting colours. Several models have been repainted at various stages resulting in inconsistent pigments within the set.
It is unclear whether the models represent a complete set, or whether this set has been made up of a single set of models.
2023.zoo.81.1: This is a round model painted in four colours.
The following is written in pencil on a white adhesive label on the wooden base: “FROG// WHOLE// I A”
The following is written in black marker on the wooden base: “VII b”
This model retains its original metal Mueller-Ward label, over which a piece of clear adhesive tape has been placed. The metal label includes a smaller white paper label upon which the following numeral is printed: “VIIb”
2023.zoo.81.2: A longitudinal section, half-round model with an oblong cavity on the upper part of its flat surface. This model has a duller, more pastel pigmentation than other models in this set.
The following is written in pencil on a white adhesive label on the wooden base: “FROG I// LS”
The following is written in ink on the wooden base: “BIII”
This model retains its original metal Mueller-Ward label, over which a piece of clear adhesive tape has been placed. The metal label includes a smaller white paper label upon which the following numeral is printed: “BIII// COPR. 1941”
2023.zoo.81.3: A longitudinal section, half-round model with an oblong cavity on the upper part of its flat surface.
The following is written in pencil on a white adhesive label on the wooden base: “FROG LI// LS”
The following is written in ink on the wooden base: “VIII”
This model retains its original metal Mueller-Ward label. The metal label includes a smaller white paper label upon which the following numeral is printed: “VIIIa// COPR. 1941”
2023.zoo.81.4: A longitudinal section, half-round model with two oblong cavities on its flat face, one larger than the other. This model has recently been repainted in bright pigments.
The following is written in pencil on a white adhesive label on the wooden base: “FROG IV// LS”
The following is written in ink on the wooden base: “BiV”
The metal Mueller-Ward label is missing from this model.
2023.zoo.81.5: A cross-sectional model with a rounded surface truncated by a flattened face. There is a divot in the upper part of the rounded surface. The flattened face has a single cavity.
The following is written in pencil on a white adhesive label on the wooden base: “FROG VIE// XS”
This model retains its original metal Mueller-Ward label. The metal label includes a smaller white paper label upon which the following numeral is printed: “BVa// COPR. 1941”
2023.zoo.81.6: A cross-sectional model with a rounded surface truncated by a flattened face. There is a divot in the upper part of the rounded surface. The flattened face has a single cavity.
The following is written in pencil on a white adhesive label on the wooden base: “FROG VII// X.S”
2023.zoo.81.7: A longitudinal section model with a rounded surface truncated by a flattened face. This model is bisected along an axis at 90° to that of the previous few models and is more elongated.
The following is written in pencil on a white adhesive label on the wooden base: “FROG VIII// LS”
The following is written in ink on the wooden base: “XVa”
The metal Mueller-Ward label is missing from this model.
Accession Number: 2023.zoo.81.1-7
Alternative Name:
Primary Materials: Plaster, Wood.
Markings of individual models are noted in the description field.
Dimensions of the square base= 10 x 10. Typical height of a model is ~14.
These models represent the stages of embryological development of the frog, an organism commonly used in biological instruction. These examples use abstracted colours to show features of the developing embryo.
A c. 1945 Mueller-Ward catalogue notes the following: “The models are not meant to supplant the actual study of the frog’s egg itself, but only to give the student certain definite ideas and a few clear landmarks so that this study may be rendered easier and more profitable.”
The paint of most of the models has been chipped with use, especially around exposed edges. A few have recently been repainted as of March 2023. This set is incomplete.
Associated Instruments:
Ward’s Natural Science Establishment, Inc., Rochester, NY.
Date of Manufacture: Mid 20th Century.
These models were used at the Department of Zoology (now part of the Department of Ecology & Evolutionary Biology and the Department of Cell & Systems Biology). As of February 2023, several have been repainted in preparation for an exhibit at the Department of Ecology & Evolutionary Biology (EEB).
The models were photographed and catalogued on Feb 6, 2023. They remain at the Department of Ecology & Evolutionary Biology.
Additional models of this type are located in the EEB teaching lab, so the two sets catalogued here (2023.zoo.80.1-11 and 2023.zoo.81.1-7) may be incomplete.
A brief biography of Justus F. Mueller (1902-1993), the developer of the models, can be found at New York Heritage Digital Collections, along with information on his personal papers at SUNY Upstate Medical University – Health Sciences Library. (Archived February 13, 2023).
Some relevant digitized catalogues can be found at “The Ward Project” website that is run by the University of Rochester. See especially Mueller-Ward models of frog embryology (c1945). (Accessed March 7, 2023)
A brief history of Ward’s Natural Science Establishment, Inc., which produced the models, can be found at the River Campus Libraries of the University of Rochester. This archive holds the company’s papers. (Archived February 13, 2023).
The models in this collection were developed by Justus F. Mueller (1902-1993), an American parasitologist educated in both art and zoology. Following his graduate research at the University of Illinois, Mueller took a position at the New York State College of Forestry (now SUNY College of Environmental Science and Forestry) in Syracuse, New York in 1929.
While at the College of Forestry, he partnered with Ward’s Natural Science Establishment, Inc. to create 16 sets of zoological models comprising 116 models.
Ward’s Natural Science Establishment was founded in 1862 by Henry Augustus Ward (1834-1906). The company supplied natural science materials to museums. In 1928, the Ward family donated the company to the University of Rochester. The company began to flourish in the 1940s and was sold to Dean L. Gamble, its president, and Frank Hawley Ward in 1940. The company became very successful during the expansion of science education in the early Cold War Period.