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CONTENTS. 



PAGE 



Tbansaotions of the Society — 



III. — Observations on the Life-Histort of Stephanooeros Eioh- 



HORNii. By T. B. Eosseter, F.R.M.S. (Plate V. Figs. 1-3) 169 

 IV. — The Peesident's Address. By Prof. P. Martin Duncan, F.R.S., 



V.P.L.S, &c .. 173 



y._ON the Mineral Cypbusite. By Julien Deby, C.E., F.R.M.S. 186 



VI.^ — ^LiST OF Desmidie^ found in gatherings made in the neigh- 

 BOiTRHooD OF Lake Windermere DURING 1883. By J. p. 

 Bisset. (Plate V. Figs. 4-7) ,. .. .. ...... ..192 



VII. — On the Formation and Growth of Cells in the Genus 



PoLYSiPHONiA. By George Massee, F.R.M.S. (Plate VI.) .. 198 



Summary of Cubrent Eesearchbs relating to Zoology and 

 Botany (peincipally Invertebrata and Cbyptogamia), Mioro- 

 sooPY, &c., including Original Communications from Fellows 



AND OTHERS .. .. .. .. 201 



Zoology. 



Development of the Optic and Olfactory Organs of Human Embryos .. .. 201 



Eggs of Birds .. .. 203 



Chemical Composition of the Egg and its Envelopes in the Common Frog . . 203 



Zoonerythrine and other Animal Pigments .. ,. 204 



Commensalism between a Fish and a Medusa - • • • • • 204 



Annelid Commensal with a Coral .. .. 204 



General Account of the MoUusca .. .. 205 



Intertropical Deep-Sea Mollusca 206 



New Cephalopoda 207 



Operculum of Gasteropoda .. - 207 



Anatomy of the Stylommatophora 208 



Segmental Organs and Podocyst of Embryonic Limacinse 209 



Spicula Amoris of British Helices . . . . 210 



Anatomy of PeUa and Tylodina .. .. 210 



Absolute Force of the Adductor Muscles of LameUibranchs 212 



Water-pores of the Lamellibranch Foot 212 



Visual Organs in Solen .... 213 



Egg and Egg-membranes of Tunicata .. .. . . . . 213 



Simple Ascidians of the Bay of Naples .. 214 



Urnatella gracilis, a Fresh-water Polyzoan 214 



Structure and Development of Argiope 215 



Genealogy of Insects 217 



Development of Antennie in Insects .. .. .... ,. 218 



Experiments with the Antenna of Insects 218 



Epidermal Glands of Caterpillars and Malachius . . .. .. 219 



Classification of Orihoptera and Neuroptera 220 



Sucking Organs of Flies .. 220 



Visceral Nervous System of Periplaneta orientalis 223 



Pulsating Organs in the Legs of Hemiptera , .. .. 224 



Vitelline Nucleus of Araneina , . 224 



Bestoration of Limbs in Tarantula 225 



Morphology of Plumicolous Sarcoptidae .. 225 



Sexual Characters of Limulus 226 



Evidence of a Protozoea Stage in Crab Development 226 



Gastric Mill of Dec^ods 227 



Spermatogenesis in Hedriophthalmate Crustacea .. ,._ 228 



Structure and Division of Ctenodrilus monostyhs 229 



Manyunhia speeiosa 231 



