Included taxa
Purcell, W. F. (1910). The phylogeny of the tracheae in Araneae. Quarterly Journal of Microscopical Science 54: 519-564. 
Species
| Species | Family | Page / figures | published as |
|---|---|---|---|
| Calculus bicolor | Orsolobidae | 527 (Df) | Calculus bicolor |
Genera
| Genus | Family | Page |
|---|---|---|
| Calculus Purcell, 1910 | Orsolobidae | 527 |