Arthropodean

…the tendency at present is to regard such stages as of hardly any importance at all. Then comparisons have constantly been made between Arthropodean and…

Source: wiktionary

Passing from the above vertebrate example to the old arthropodean type Periplaneta we find, as fig. 5 and the table on p. will show, that here the number of the types of gemini is reduced from six to five.

Source: wiktionary

Briefly the author endeavours to prove that vertebrates are derived directly from arthropods, that the arthropodean alimentary canal is represented by the ventricles of the brain and the central canal of the spinal cord, the pituitary body and embryonic pharynx represent the mouth of the arthropod, and the neurenteric canal the primitive anus.

Source: wiktionary

1955: AUTHOR UNKNOWN, Research films, p429 or 119 (sources contradict) — MENTION ONLY (888) MANTON, S. M. The Evolution of Arthropodean Locomotory Mechanisms. Part I. The Locomotion of Peripatus. J. Linn. Soc. (Zool.) 1950, 41, 529.

Source: wiktionary