. The anatomy of the common squid, Loligo pealii, Lesueur. Squids; Mollusks. 69 statocysts whereas the visceral ganghon lies above the statocysts and behind the r^st of the ring, blocking the oesophageal canal so that the oesophagus makes a sharp turn upward to pass above this ganglion. The upper and posterior surfaces of the visceral ganglion are covered by a fascia which extends from the edges of the large foramen of the skull to the oesophagus and so separates the brain and the oesophageal canal from the liver. The cerebral ganglion gives off two pairs of connectives, the cerebropedal and t
. The anatomy of the common squid, Loligo pealii, Lesueur. Squids; Mollusks. 69 statocysts whereas the visceral ganghon lies above the statocysts and behind the r^st of the ring, blocking the oesophageal canal so that the oesophagus makes a sharp turn upward to pass above this ganglion. The upper and posterior surfaces of the visceral ganglion are covered by a fascia which extends from the edges of the large foramen of the skull to the oesophagus and so separates the brain and the oesophageal canal from the liver. The cerebral ganglion gives off two pairs of connectives, the cerebropedal and the cerebro-buccal. The former pass downward and forward around the oesophagus to the propedal ganglion, the latter pass forward above the oesophagus to the suprabuccal ganglion. This gang- lion also receives a connective from the propedal ganglion (propedo-buccal connec- tive) and gives off a connective which passes around the oesophagus to the in- frabuccal ganglion. A long pair of connec- tives passes from the infrabuccal ganglion to the splanchnic ganglion. A short large bundle of fibres passes from the pedal to the propedal ganglion, which also receives the above mentioned connectives (cerebro-propedal and propedo- buccal connectives) and gives off five pairs of connectives to the five pairs of brachial ganglia. Connectives unite the first and second, the second and third, the third and fifth brachial ganglia, and with the commissures between the gang- lia of the first pair and the fifth pair form the branchial nerve-ring. Careful search has failed to reveal any connection between the ganglia of the fourth arms (tentacles) and this ring. The pleural ganglion, viewed externally, is well marked and is readily distinguished from the cerebral ganglion on one hand and from the pedal and visceral ganglia on the other, but a study of the minute anatomy of the so oalled ganglion shows that there is very little ground for calUng the mass of fibres in which a few nerve cells are scat
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectmollusks, bookyear191
