. A biology of Crustacea. Crustacea. ii4 A BIO L O G Y OF CRUS T A C E A and the main artery, while L. obtusa restricts its point of attach- ment to the artery itself, sometimes not actually entering the main artery, but one of the branches to the gills. It has been suggested that the copepods find their way into the arteries by responding to the vibration produced by the beating of the fish's heart. It would follow from this that the two species have slightly different responses, L. brancliialis tending to go nearer to the heart. BRANCHIURA All the members of this small order are parasites. T
. A biology of Crustacea. Crustacea. ii4 A BIO L O G Y OF CRUS T A C E A and the main artery, while L. obtusa restricts its point of attach- ment to the artery itself, sometimes not actually entering the main artery, but one of the branches to the gills. It has been suggested that the copepods find their way into the arteries by responding to the vibration produced by the beating of the fish's heart. It would follow from this that the two species have slightly different responses, L. brancliialis tending to go nearer to the heart. BRANCHIURA All the members of this small order are parasites. The genus Argulus (fig. 50) is the best known, and is remarkable for the development of a large pair of adhesive suckers in place of the first maxillae. Most of the species are only about a quarter of an inch long, but A. scutiformis reaches a length of over an inch. These creatures attach themselves to the skin of fishes; they have also been recorded on frog tadpoles, axolotls and the tadpoles of the smooth newt Triturus vulgaris. They are not. permanent parasites, and may frequently be found swimming freely. The genus Chonopeltis, however, has lost the ability to swim and dies in a couple of days when removed from its host. PfiOAOSCH. 4-TH THORACIC LEG SPEOMATHEC/t 1st MAXHL/t 2HO MAXILLA ABDOHEN Fig. 50. Argulus foliaceus (Branchiura), adult female, found swimming freely in Regents Park Lake. Actual length about 5 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 Green, J. (James), 1928-. Chicago, Quadrangle Books
Size: 1551px × 1612px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbiodiversit, booksubjectcrustacea
