Appendages. The swimming leg, the only appendage observed, is relatively short, twice as long as the carapace. The coxa and second segment have not been seen. The third is short and ring like, the fourth tubular, long, slender (two and one half times as long as wide) and slightly curved. The next is again shorter (half as long as preceding) and also tubular, slightly widening distally. The sixth is of the same length with the fifth and elongate pentagonal in outline. Like the following segments it bears two broad leaflike spines of greater length than the segment. The seventh and eighth segments are of similar length but broader; apparently of inverted cuplike outline but obscured by the overlying spines, which give the terminal part of the leg the appearance of a bud-bearing twig. The last joint is apparently subdivided into three bractlike lobes, the middle of which is the longest.
No traces of the ornamentation of the test are shown.
| Measurements | millimeters | |
| Length of carapace | 10.8 | |
| Greatest width | 10.2 | |
| Least width | 8.2 | |
| Length of eyes | 2.4 | |
| Length of first tergite | 1.0 | |
| Width of same | 8.4 | |
| Length of third tergite | 2.2 | |
| Width of same | 9.4 | |
| Exposed length of swimming leg | 16.5 | |
| The largest carapace observed measures | ||
| Length of carapace | 17 | |
| Greatest width | 16.3 | |
| Least width | 15 | |
| Length of eyes | 4 | |
Horizon and locality. In the Shawangunk grit of Otisville, N. Y.
Observations. We have already noted the stylonuroid features of the carapace of this species. The spadelike form of the carapace is also
