Tom Turpin
Professor of
Purdue University


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Flies in the face of fashion

What's Buggin You Now?





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Insect pieces and parts

morphology poster
photo credit: John Obermeyer

Morphology has to do with form and structure. The word is based on the Greek word morph, denoting a specified form or shape. Biologically, it is that branch of science that deals with the form of living organisms. In linguistics, it has to do with word structures, in geology, the structure of rocks.

In popular culture, the term describes a special effect - or seamless transition - in motion pictures. There was a plasticine TV character called Morph. In the mid 1990s, the Mighty Morphin Power Rangers were popular toys that could be changed from one form to another.

Insect morphology, as you might have guessed, is the study of the form and structure of insects. Students of entomology study the morphology of insects to help identify species and to understand the relationship between form and function.

Some insect morphology is included in almost any introductory material to the insect world. Such information might include basic concepts, such as the fact that an insect has three major body divisions: head, thorax and abdomen. The information can be more complex and include the structure of different types of antennae, with names for the component parts of such structures.

There are entire books devoted to the pieces and parts that make up body structure of insects. Robert Evans Snodgrass published one of the first major books devoted entirely to insect morphology in 1935. This book, "Principles of Insect Morphology" has been the standard text for insect morphology classes for many years, and illustrations from the book have been adapted for a number of other books on entomology.

insect parts chart
Illustration from "Principles of Insect Morphology"

Snodgrass majored in zoology at Stanford University, where he studied under entomology professor Vernon Kellogg. Kellogg was a leading U. S. entomologist who, in a did-you-know footnote, taught an insect-science class at Stanford that was taken by future U.S. President Herbert Hoover.

After completing his bachelor's degree at Stanford, Snodgrass accepted a teaching position at Washington State College. His practical jokes were too much for the authorities at the college, so he returned to Stanford as an instructor in entomology. There, too, he got into trouble and was dismissed from the faculty. The reason? He defied an administrator's orders to not strip the leaves from the campus mulberry trees. Snodgrass was using the leaves to feed his colony of silkworms, and the leafless trees died.

Snodgrass then moved to San Francisco and worked for an advertizing agency and attended art school at night. He endured the San Francisco earthquake before moving across the country to Washington, D. C., where he worked for the Bureau of Entomology for a few years. He left Washington, D. C. for New York City, where he continued his art studies and then, at the request of a friend, he moved to Indiana.

In Indiana, Snodgrass sold paintings to farmers, a venture that didn't turn out to be financially successful. But it did provide him an opportunity to observe Hoosiers, which he depicted in his unpublished "Indiana Sketch Book." According to Ernestine B. Thurman in an article about Snodgrass: "It would appear from his sketches that the males of the day were chiefly remarkable for growing whiskers, loafing in groups according to age and length of beards, chewing tobacco, and distance and accuracy of expectoration; the females for cooking, rearing large families, and acquiring physiques that looked like feather pillows tied in the middle."

While in Indiana, Snodgrass one day casually dropped into the office of the State Entomologist in Indianapolis. He was offered an opportunity to join the staff, due to a need for an artist to illustrate publications. In the two years he spent with the office, he also wrote "Some of the Important Insect Pests of Indiana" and produced oil-painting wall charts of farm and garden pests. The pests of Indiana article is included in the ninth annual report of the Indiana State Entomologist.

In 1917, Snodgrass left Indiana and returned to Washington D. C. where he was associated with the federal government, until he retired in 1945. He also taught entomology at the University of Maryland from 1924 until 1947, where it is said he sketched very rapidly while he spoke. Probably not surprising for a man who developed an international reputation for drawing insects and their pieces and parts!


Writer: Tom Turpin
Editor: Olivia Maddox