The Canadian journal of industry, science and art . MINERALS AND GEOLOGY OF CANADA. 119 the class G-asteeopoda. They constitute however a truly aberrantgroup, having affinities with the Pteropods on the one hand, andwith both Q-asteropods and Cephalopods on the other. Existingforms, like the pteropods, are of pelagic habit, swimming, by meansof a fin-like appendage, in the open seas. The swimming organ is amodification of the gasteropod foot: see below. Some are withouta shell, whilst others secrete one of a fragile and delicate

---

Size: 2497px × 1001px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ., bookcentury1800, bookdecade1850, bookpublishertoron, bookyear1856