FRESH FACTS. 



Memory in Fishes. L. Edinger. " Haben die Fische ein Gedachtnis 1 " 

 Das Ergebniss einer Sammelforschung mitgetheilt in der neurologischen Sektion 

 der Versammlung Deutscher Naturforscher und Aerzte in Miinchen, 1899. 

 Sonderabdruck aus der Beilage zur AUgemeinen Zeitung, Nos. 241 and 242, 

 vom 21 und 25 Oktober 1899. Miinchen, 30 pp. We have been favoured 

 with a copy of this interesting paper, embodying the results of observations 

 which have been communicated to Prof. Edinger since he made his appeal 

 for information a couple of years ago. It seems to be clear (1) that the 

 instinctive impulse to flee from certain impressions may be lessened as the 

 fishes find the stimulus harmless and become accustomed to it, and, contrariwise, 

 that they may become shy ; (2) that the optic or chemical stimulus normally 

 associated with food may be replaced by the image of the feeder. There is 

 therefore a kind of memory, but it is very different from that of mammals. It 

 may be recalled that Prof. MTntosh, of St. Andrews, was one of those who 

 answered the question, "Have fishes a memory'?" with a decided affirmative, 

 when the matter was discussed a couple of years ago. 



More Traces of Neomylodon. Erland Nordenskiold. " Neue 

 Untersuchungen fiber Neomylodon listai," Zool. Anzeig. xxii. 1899, pp. 335- 

 336. The author has made laborious excavations in the cave at Ultima 

 Esperanza (South Patagonia), where previous digging discovered the pieces of 

 skin, etc., belonging to the somewhat shadowy creature, Neomylodon listai. 

 He has found a number of bones which he thinks should go with the skin. 

 Their description will be awaited with interest. 



Concerning an Ancient Fish. A. Smith Woodward. "Note on 

 Scapanorhynchus, a Cretaceous Shark apparently surviving in Japanese Seas," 

 Ann. Nat. Hist. iii. 1899, pp. 487-489. A shark in all essential respects 

 identical with the supposed extinct genus Scapanorhynchus has been obtained 

 from the deep sea off Yokohama, and described by Profs. D. S. Jordan and 

 Mitsukuri. It has been called 31 itsukurina, but Mr. Smith Woodward points 

 out that in all the generic characters which can be compared it agrees with the 

 above-named predaceous shark of the Cretaceous Seas. 



Rule of the Nucleus. Jacques Loeb. "Warum ist die Regeneration 

 kernloser Protoplasm astiicke unmoglich oder erschwert 1 ?" Arch. Entwiclcelungs- 

 mechanik, viii. 1899, pp. 689-693. In this paper, which the author has been 

 kind enough to send us, there is a fresh suggestion rather than a fresh fact. 

 The suggestion is that the nucleus is the oxidation-organ of the living substance, 

 and that non-nucleated fragments of cells are incapable of regeneration because 

 the oxidation-function has sunk below the required minimum. The fragments 

 gradually die of asphyxia. This should be compared with the observations of 

 Schenk referred to in another part of this number of Natural Science. 



A Contribution to Experimental Embryology. Jacques Loeb. "Ueber 

 den Einfluss von Alkalien und Sauren auf die embryonale Entwickelung und das 

 Wachsthum," Arch. EntwickelungsmecJianiJc, viii. 1899, pp. 631-641, 1 pi. 

 Experiments on the developing larvae of the sea-urchin Arbacia show that even 

 extremely minute additions of sodium hydrate solution to the sea-water hasten 

 the development and growth, while acids have the reverse effect. The reason 

 suggested is that weak alkalies promote the oxidation-processes and therefore the 

 synthetic processes in the living substance. 



A Triassic Cuttlefish. K. Picard. "Ueber Cephalopoden aus dem 

 unteren Muschelkalk bei Sondershausen " (Zeitschr. deutsch. geol. Ges. li. 

 pp. 299-309, pi. xvi. Oct. 1899) describes Campylosepia triasica, n.g. et sp. on 



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