558 Prof. R. Burckhardt on the 



Lifei-ature cited. 



Cartkr, II. J. (1858.) — "On Fecuudiition in Eudorina elegans and 



Cryptoglena,^' Ann. & Mag. Nut. Hist. ser. 3, vol. ii. pp. 237-253, 



pi. viii. 

 . (1871.") — " Note on a Freshwater Species of Cerntium from the 



Lake of Nynee (Naini) Tal in Kumaon," Ann. & Mag. Nat. Hist. 



per. 4, vol. vii. pp. 229, 2;iO. 

 Garman, H. (1890.) — '• A Preliniinarv Report on the Animals of the 



Missi.s.'sippi Bottoms nearQuincy, Illinois, in August 1888," Part I., 



Bull. 111. State Lab. Nat. Hist. vol. iii. pp. 123-184. 

 KoFOiD, C. A. (1898.)—" Plankton Studies, II. On PlcocJorina ilh'tiois- 



msis, a new Species from the Plankton of the Illinois Piiver,"' Bull. 



111. State Lab. Nat. Hist. vol. v. pp. 273-293, pis. xxxvi., xxxvii. 

 ScHKODEE, B. (1898.) — " Dangeardia, ein neues Chytridineen Genus 



auf Pandorina morum, Bory," Ber. d. deutsch. Bot. Gesellsch. 



Jahrg. 1898, Bd. xvi. pp. 314-321, Taf. xx. 



EXPLANATION OF PL.\TE VU.* 



Fig. 1. Platydorinu coudata, face view of 32-cell colony, X 550. 

 Fig. 2. Face view of 1 6-cell colonv, X 628. 

 lig. 3. Edge view of 32-cell colony, X 350. 

 Fig. 4. Lateral view of one of the marginal cells, x 1400. 

 Fig. 5, a-e. Outline of the posterior ends of several deformed colonies, 

 X 280. 



LXXIT. — On the Luminous Organs of Selachian Fishes. By 

 RUD. BuECKHARDT, Nat. Hist. Mus., S. Kensington. 



In the ' Zeitsclirift fiir wissenschaftliche Zoologie,' vol. Ixvi. 

 1899, Johann, at the instigation and under the guidance of 

 Prof. Blochniann, of Tubingen, published a paper entitled 

 " Ueber eigenthiimliche epitheliale Gebilde (Leuchtorgane) 

 bei Spinax niger^'' in which are given the results of some 

 researches he made in this subject. 



In this paper he describes some very minute organs with 



* Figures drawn by C. A. Kofoid and inked by Miss L. M. Hart. 



