248 NOTES AND MEMORANDA. 



the months mentioned. On November 9th^ in the product 

 of a tow-net taken by me south-east of the Eddystone, there 

 were a number of buoyant fish eggs, which hatched two 

 days after in my workroom on shore. The young fish 

 hatched from these exhibited three characters, which are 

 also found in the newly-hatched herring : (1) The yolk, 

 instead of being homogeneous as in most buoyant ova, was 

 composed of a number of distinct yolk-spherules ; (2) The 

 notochord was unicolumnar, that is, contained a single linear 

 series of vacuoles as in the heri'ing, not several series side 

 by side as in young flat-fishes and others ; (3) The anus 

 was separated by a long interval from the yolk, and placed 

 near the end of the tail, as it is in the newly-hatched 

 herring, while in most fishes it is immediately behind the 

 yolk. It is possible enough that these buoyant eggs are 

 those of the pilchard, in which case the close similarity of 

 the fish hatched from them to the young herring* would be 

 explained, although the proof of the fact that the ova of the 

 pilchard are typically buoyant and pelagic, while those of 

 the herring are typically adherent ova, would be very sur- 

 prising. I earnestly hope that during the present winter I 

 may obtain some pilchards in spawning condition, in which 

 case, by taking and fertilizing some ova, I should be able to 

 decide the interesting questions implied in the above discus- 

 sion. There are some grounds for saying that it is possible 

 the ova of the sprat are buoyant, although it would be natu- 

 rally expected that all the species of Clupea deposited adhe- 

 sive eggs like those of the herring. 



Reproductive Organs of the common Sole. — On November 

 12th I dissected four soles {Solea vulgaris, Quensel) in order 

 to examine the reproductive organs. The soles were bought 

 by the Laboratory attendant from a fish buyer, and there- 

 fore could not well have been selected in any way, except that 

 they were all moderately large. Two were males and two 

 females. 



In one female, which was fourteen inches long, including 

 the tail, I opened first the long posterior extension of the 

 body cavity on the right, dark, and upper side. When the 

 skin was laid open, without further dissection, four parallel 



