William Lundbeck: Some remarks on the eggs and egg-deposition of Halobates. 7 



No. 14. A Sepia-shell with a little more than a hundred eggs. 4° 56' Lat. N., 106° 6' 

 Long. E. 22/^ 1881. Hartmann. (PI. I, fig. 5). 



- 15. A small piece of sea-weed with eggs. 1° Lat. N., 106° 40' Long E, 1869. 



Andrea. 



- 16. A Sepia-shell with half a hundred eggs. 3° 20' Lat. S., 106° 50' Long. E. 1869. 



Andrea. 



- 17, A Sepia-shell with several hundreds of eggs, most of them either containing 



embryos or open and empty. Ghinese Sea between 4° and 8° Lat. N. 1866. 

 Gaspersen. 



- 18. A small piece of floating timber with eggs and larval skins. 4° 30' Lat. N., 



137° Long. E. »/j 1875. Gaspersen. 



- 19. A small piece of vegetable substance with about half a hundred eggs, some 



with embryos, ca. 10° Lat. S., 142° Long. E. 1881. Gorneliussen. 



- 20. A piece of a feather with eggs, all with embryos. The Galapagos Islands. 



Received from Dohrn. 



Of the 20 specimens named here, four are missing, namely No. 3, 8, 15 and 18 ; 

 these are noted in the above list according to a card-catalogue, written by Steen- 

 STRUP ; as Steenstrup was thoroughly acquainted with Halobates-eggs, there is no doubt 

 about the mentioned specimens being correctly referred by him. 



In the existing material we can distinguish between live different sorts of eggs, 

 which thus must belong to at least five different species of Halobates; (perhaps to 

 more, as several species may have quite similar eggs). In all the specimens, whether 

 they show few or many eggs, all the eggs are similar, and there is nothing which 

 indicates that the females of different species have laid their eggs together. All the 

 eggs from the Atlantic localities as well as No. 10, Red Sea, No. 12, 3° 10' Lat. S., 

 89° 51' Long. E., and No. 20, Galapagos Islands agree, and may thus belong to one 

 species (PI. I, fig. 6). They have a length of about Imm and a diameter of about 

 0,4 mm, are of an elongated oval shape and as usual with the ventral side more 

 arched than the dorsal one, and with the front end a little broader than the posterior. 

 The egg-shell is not thick, and shows no special structure. In the Atlantic five 

 species of Halobates occur, but only one of them is common, viz. H. Wullerstorffi 

 Frauenf., which according to Witlaczil (1. c.) and Dahl (Ergebnisse d. Plankton-Exp. 

 II, 9 a, «, 6) is identical with H. micans Esch., and this species also appears in the 

 Indian Sea and the northern Pacific; there is thus some reason for beHeving, that 

 the eggs in question belong to this common species. Its eggs are, as mentioned, de- 

 scribed and figured by Buchnan White, who describes the shell without structure, 

 and States the length to be 1,2 mm and the breadth 0,8 mm; this breadth is, as 



