EGGS AND LARV^l OF TELEOSTEANS. 135 



1 885. Miecz v. Kowalewski. Furch. und Keimblatteranlage der Teleostier, S. B. der physik. medicin. 



Societal, Erlangen, 1 5th. Dec. 



1886. Miecz v. Kowalewski. Ueber die ersten EntwickL processe der Knochenfische, Z. f. wiss. 



Zool., Bd. xliii. 

 1886. Miecz v. Kowalewski. Gastrulation und Allantois bei den Teleostiern, S. B. d. phys. med. 



Societat, Erlangen, June 7. 

 1880. Carlo Emery. Fauna and Flora des Golfes von Neapel.— IF e . Monographie, Fierasfer. 

 1880. A. C. Gunther. Art. "Ichthyology," Ency. Britannica. 

 1880. A. C. Gunther. Introduction to Study of Fishes, Edinburgh. 

 1880-84. Francis Day. British Fishes, London and Edinburgh. 



DESCRIPTION OF PLATES. 

 Plate I. 



Fig. 1. Egg of herring towards the close of period of simple segmentation, 11 hours after fertilisation. 



Aug. 26, 1884. Zeiss A, Oc 3. 

 Fi"'. 2. Anterior end of herring embryo, 6 days after fertilisation, 1 day before hatching. Sept. 1, 



1884. Zeiss A, Oc 3. 

 Fig. 3. Herring larva nearly 24 hours after hatching. Aug. 22, 1884. Zeiss A, Oc 2. 

 Fig. 4. Outline of alevin of Salmo levenensis, 3 days after hatching. Magnified about 4 times. 

 Fig. 5. Ovum of Osmerus eperlanus, Lacep, 25 J hours after fertilisation. May 7, 1886. Mag. 



33 times. 

 Fig. 6. Ovum of Os. eperlanus : optical section through suspensory membrane, internal zona, and 



micropyle. Zeiss CC, Oc 2. 



Plate II. 



Fig. 1. Embryo of Pleuronedes platessa, Linn., in ovo, 23 days 5 hours after fertilisation. Mag. 33 

 times. Feb. 26, 1886. 



Fig. 2. Sculpturing of surface of vitelline membrane of ovum of PI. platessa, L. Mag. 50 times. 



Fig. 3. Larva of PL platessa, taken artificially from ovum on point of hatching. 27 days after fertili- 

 sation. Mag. 33 times. 



Fig. 4. Ovum of PI. flesus, 2 days 2J hours after fertilisation. Mag. 33 times. The development of 

 this egg was retarded : end of the period of simple segmentation. 



Fig. 5. PL flesus, 22 hours after fertilisation, stage just before appearance of segmentation cavity. 

 Mag. 33 times. March 31, 1886. 



Fig. 6. PL flesus, 2 days 2J hours. First appearance of segmentation cavity. Mag. 33 times. 



Fig. 7. PL flesus, 2 days 22 hours. Mag. 33 times. 



Fig. 8. PL flesus, newly hatched. 7 days. April 6, 1886. Pigment black, anus open. Mag. 33 times. 



Fig. 9. Ovum of Pleuronedes limanda, L., 20J hours after fertilisation. Stage preceding formation of 

 segmentation cavity. May 22, 1886. Mag. 33 times. 



Fig. 10. Blastoderm of unfertilised ovum of PL limanda, showing expulsion of polar globule. 



Fig. 11. Spermatozoon of PL limanda. Zeiss DD, Oc 4. 



Plate III. 



Fig. 1. Newly shed unimpregnated ovum of PL limanda, optical section showing micropyle and rela- 

 tions of protoplasmic layer. Zeiss A, Oc 3, Abbe's camera. Mag. 70 times. 



Fig. 2. PL limanda, J hour after fertilisation. Zeiss A, Oc 3, camera. Mag. 70 times. 



Fig. 3. PL limanda, 1-|- hours after fertilisation. Mag. 70 times. 



Fig. 4. PL limanda, 3 hours after fertilisation. Mag. 70 times. 



Fig. 5. PL limanda, little more than 3 hours : process of first division. Mag. 70 times. 



Fig. 6. PL limanda, larra newly hatched. May 28, 1886. Mag. 33 times. 



Fig. 6a. Notochord of same. Zeiss CC, Oc 3. 



Fig. 7. Blastodisc of PL cynoglossus, unfertilised 2 hours after shedding, shows what may be the 

 second polar body. Mag. 70 times. 



