Mr. E. H. L. Schwarz on Coccoliths. 345 



minifera, such as Globigerina *, and later f he figured them 

 joining into linear aggregates to form Nodosaria or in alter- 

 nate lines to form Textularia ; but I have not been able to 

 see from his figures whether he is dealing with the conven- 

 tional coccospheres or really Foraminifera, in the external 

 sarcode of which the discoliths have become imbedded; for 

 he says the latter are arranged at regular intervals over the 

 surface of the former. 



When I first worked out the above details, some eighteen 

 months ago, Prof. Judd, to whom I am indebted for much 

 help, threw doubt on my results, because they were derived 

 from fossil forms, while nothing of the kind had been seen 

 in the recent ones, even when treated with greater skill and 

 with better instruments than I could command; but I have 

 gone over all the work again lately, and I can only conclude 

 that the protoplasm of the recent ones obscured the details 

 of their internal structure. 



To recapitulate my results, then : — 



The discolith represents the adult stage of the coccolith, 

 and is a separate organic individual consisting of a phosphatic 

 disk surrounded apparently with protoplasm. When they 

 wish to reproduce themselves the protoplasm surrounds itself 

 with a calcareous envelope consisting of two cups, one deep 

 and enclosing the discolith, the other functioning as a lid. 

 Division of the discolith then proceeds irregularly till some 

 sixteen or more minute bodies, representing embryonic disco- 

 liths, are formed ; the cups then separate and set their contents 

 free in a mass. The latter then continue to grov^, retaining 

 the cup-like form of the cyatholith, and constitute the cocco- 

 spheres of Wallich, Huxley, and H^ckel ; finally the colony 

 is disbanded, and the discoliths float about freely on the 

 surface of the ocean. 



As to their nature, I think there can be no doubt as to their 

 being organic, and that they belong to that class of organisms 

 which the zoologist and botanist have equal right in claiming 

 to belong to his favourite kingdom ; but they seem to have a 

 preponderance of botanical resemblances, and may be put 

 provisionally among the Phycochromacese, near to Gloeocapsa^ 

 Chroococcus^ &Q,., to which they seem to be allied by their 

 reproduction. 



As to their name, though Ehrenberg's morpholith undoubt- 

 edly preceded Huxley's coccolith, he used the word as descrip- 

 tive and one which could, with equal propriety, be applied to 



* Ann. & Mag. Nat. Hist. 1860, vi. p. 4o7. 

 t Ibid. 1862, ix. p. 30. 



