. The Cambridge natural history. Zoology. 128 CRUSTACEA PEKACARIDA (Asellidae) being extremely abundant all over Europe in weed- grown ditches, the mud of slowly moving streams, and even on the shores of large lakes. They are mostly sluggish in habit, but the marine Munnopsidae (Fig- 83, Mannopds) are expert swimmers, the swimming organs being fashioned by the expansion and elongation of the thoracic legs. Sub-Order 5. Oniscoida. The Oniscoida ^ are terrestrial forms in which tlie abdomen is fully segmented, the pleopods are respiratory, their endopodites being delicate branchiae, while their
. The Cambridge natural history. Zoology. 128 CRUSTACEA PEKACARIDA (Asellidae) being extremely abundant all over Europe in weed- grown ditches, the mud of slowly moving streams, and even on the shores of large lakes. They are mostly sluggish in habit, but the marine Munnopsidae (Fig- 83, Mannopds) are expert swimmers, the swimming organs being fashioned by the expansion and elongation of the thoracic legs. Sub-Order 5. Oniscoida. The Oniscoida ^ are terrestrial forms in which tlie abdomen is fully segmented, the pleopods are respiratory, their endopodites being delicate branchiae, while their exopodites are plate-like and. Flu. 84.—Llgia ocmnica, ventral and dorsal views, x 1. (From original drawings prepared for Professor Weldou.) form protective opercula for the gills, and the uropods are biramous and not expanded. The epimera of the segments are greatly produced. The terrestrial Isopods, although air- breathers,^ are dependent on moisture, and are only found in damp situations. ^ It seems probable that they have been derived from marine Isopods, since the more generalised of them, , Ligia (Fig. 84), common on the English coasts, are only found in damp caves and crannies in the rocks. ' A useful little book on British Woodlice by AVebb and Sillem (1906) may be lirofitably consulted. Budde Lund's Isopoda Terrostria, 1900, is useful to the specialist. ~ The pleopods are traversed by a system of minute tubes called pseudotracheae, somewhat resembling the tracheae of Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Harmer, S. F. (Sidney Frederic), Sir, 1862- ed; Shipley, A. E. (Arthur Everett), Sir, 1861-1927. ed. [London, Macmillan and Co. , Limited; New York, The Macmillan Company
Size: 2009px × 1244px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1895
