ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



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Chiltonia. Only one species is known. The genus may be defined as 

 follows : — Mandible without definite molar tubercle. First maxilla with 

 palp absent or vestigial, inner lobe small and without plumose setfe. 

 First gnathopoda small and subchelate in both sexes ; second gnathopoda 

 large and chelate in the male, subchelate in the female. Third uropoda 



Ceina egregia. Dorsal view of female. 



represented by a small rounded lobe. Telson formed of a thick plate, 

 partially cleft. The animal occurs on New Zealand coasts, at the roots 

 of seaweeds, generally about low-tide mark. It is protectively coloured. 



Its length is 6 to 7 mm. 



J. A. T. 



Redescription of Orchestia tucurauna Fritz Miiller. — Chas. 

 Chilton (Ann. Mag, Nat. Hist., 1919, 3, 376-86, U figs.). This 

 species occurs both in South America and in New Zealand, an instance of 

 a not uncommon distribution among Crustacea. It occurs in brackish 

 or fresh-water. The author gives an adequate description, with good 

 figures. J- A. T. 



Reactions of Land Isopods to Light. — Charles H. Abbott {Journ. 

 Exper. ZooL, 1918, 27, 193-246, 14 figs.). Experiments with Onisctis 

 asellus, Porcellio ratkei, and F. scaber show that land Isopods respond 

 to light stimuli by photokinesis, by phototaxis, and to a slight degree 

 by vision. Phototactic reactions were studied. Oniscus is negative to 

 diffuse daylight and to controlled horizontal illumination by artificial 

 light. Porcellio is less consistently negative. The response wag the 

 same to all intensities from 100 candle metres to 0"01. No consistent 

 change in the phototaxis of Oniscus was caused by repetition of stimuli, 

 by previous exposure to strong light or weak, by maximum or minimum 

 of moisture. Porcellio was somewhat less negative after living in a dry 



