Report on the Lancashire Sea-Fisheries at the University of Liverpool, and the Sea-Fish Hatchery at Piel (Volume 12) (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1904. Excerpt: ... Appendix. M E M 0 I K ON A R E X I ( 0 L A. The Fisherman's Lug worm. By J. H. Ashworth, D.Sc. (Lecturer in Tnrertebrate Zoology in the University of Edinburgh.) Contexts. PAGE. Introduction: Habits; Varieties; Distribution 130 External Characters: Segmentation; Parapodia; External Apertures; Gills; Setae; Epidermis; Pigment 133 General Anatomy 147 Musculature 149 Ccelom And Cozlomic Fluid 151 Alimentary Canal: Burrowing 154 Vascular System: Heart and Heart-body 159 Nephridia 164 Reproductive Organs 170 Nervous System: Brain; CEsophageal Connectives; Ventral Nerve-cord; Giant Cells and Giant Fibres 173 Sense Organs: Otocyst; Nuchal Organ; Eyes; Prostomium... 179 Development 183 Post Larval Stages 188 Systematic Position and Classification 196 Parasites 207 Directions For Practical WortK 208 Economic Section 21 ) Description or Plates...,, ., . 229 K Introduction. Arenicola is a genus of abundant and widelyranging Polychaet worms, represented in the British fauna by three species, all of which may be found between tide marks in the neighbourhood of Port Erin (Isle of Man) and Plymouth. The common lugworm, Arenicola marina, forms a convenient type of the genus. It is abundant on most of the sandy shores around the British Isles. Its presence is indicated by the small heaps or coiled castings of sand, which are familiar objects between tide marks. The animal may be found on digging to a depth of one to three feet near such castings, and it is commonly so obtained by fishermen, by whom it is extensively used as bait.J Its general appearance may be seen in Fig. 1. It is almost invariably slightly inflated in the anterior region, being widest at a point about one-sixth of its length from the anterior end. Habits, Varieties. There are on the Lancashire coast...