SEA-FISHERIES LABORATORY. 489 



oe. ai. — Antero -inferior dilator muscle of the oesophagus. 



oe. as. — Antero-superior dilator muscle of the oesophagus. 



oe. I. — Lateral dilator muscle of the oesophagus. 



o. e. m. — Outer flexor muscle of the first maxilla. 



oe. p. — Posterior dilator muscle of the oesophagus. 



o. ex. — Outer flexor muscle of the scaphognathite (p.ex.s., Figs. 27, 31;. 



o. f. — Outer extensor muscle of the scaphognathite. 



o. /. m. — Outer extensor muscle of the first maxilla. 



o. g. — Optic ganglion. 



o. I. s. — Outer lamellar sinus. 



o. m. c. — Ophthalmic muscle chamber. 



o. m. ex. — Outer median flexor muscle of the scaphognathite. 



o. m. f. — Outer median extensor muscle of the scaphognathite. 



om. n. — Oculo-motor nerve. 



o. n. — Optic nerve. 



o. n. fib. — Optic nerve fibres. 



op. — Operculum of excretory opening. 



op 1 . — Inner side of operculum. 



op. b. s. — Ophthalmic blood sinus. 



o. ped. — Optic peduncle. 



o. py. — Pyloric ossicle. 



orb. — Orbit. 



ov. — Ovary. 



ov. art. — Ovarian artery. 



ovd. — Oviduct. 



P. — Propodite. 



P. 1—4.— Walking legs 1 to 4. 



p. 1 — 2. — 1st and 2nd abdominal appendages of male. 



p. ace. —Posterior accessory muscle of the scaphognathite, 



p. c. p. — Pro-cephalic processes. 



pec. — Pectineal ossicle. 



ped. — Eye peduncle. 



Per. — Peric ardium . 



per. gl. — " Pericardial pouch." 



p. ex. B. — Tendon of the posterior extensor muscle of the basi-ischiuin 



p. f. B. — Tendon of the posterior flexor muscle of the basi-ischium. 



p. g. — Par oesophageal ganglion. 



pg. c. — Pigment cell. 



pg. i. — Inner pigmented layer of the eye. 



p. g. n. — Posterior gastric nerve. 



pg. o. — Outer pigmented layer of the eye. 



pig. I. — Pigment layer. 



pi. art. — Postero -lateral artery. 



p. lb. — Progastric lobe of the bladder. 



p. mes. — Posterior mesopyloric ossicle. 



p. n. — Postero-lateral nerve. 



pod. br. — Podobranch. 



p. o. lb. — Post- oesophageal lobe of the bladder. 



p. ost. — Posterior ostia of the heart. 



pp. — Pie uro pyloric wall. 



p. pec. — Prepectineal ossicle. 



prot. — Protopodite. 



pr. p. — Propyloric ossicle. 



p. 8. a. — Posterior supra-ampullary ossicle. 



pt. c. — Pterocardiac ossicle. 



pt. pec. — Post- pectineal ossicle. 



pyl. — Pyloric region of the fore-gut. 



py. lat. — Lateral pyloric muscles. 



