Mr. H.J. Carter on the Cell-contents of the Characese. 101 



Fig. 13. Leperditia marginatal (young?), outline of the anterior aspect 



of the two valves united. 

 Fig. 14. Leperditia marginaia ? (adult) : a, cast of left valve ] b, the same, 



dorsal aspect ; c, the same, ventral aspect ; d, anterior aspect. — 



British Museum. 

 Fig. 15. Leperditia marginata"?, cast of right valve. — Museum of Practical 



Geology. 

 Fig. 16. Leperditia Solvensis, artificial cast of impression of right valve. — 



Museum of Practical Geology. 



IX. — Further Observations on the Development of Gonidia (?) 

 from the Cell- contents of the Characese, and on the Circulation 

 of the Mucus-substance of the Cell. By H. J. Carter, Esq., 

 Assistant Surgeon H.C.S., Bombay. 



[With two Plates.] 



Since my first " Observations on the Development of Gonidia (?) 

 from the Cell-contents of the Characese/^ &c.* were arranged, 

 and which I then stated were not so " extended and complete " 

 as they would have been had more leisure been at my disposal, 

 I have obtained much more precise information on the subject. 

 The inquiry was then new to me, and the only author to my 

 knowledge who had engaged in it was Professor Pringsheim, 

 who met with a similar formation in Spirogyray &c.t, and had 

 assumed, as the simplest way of accounting for it, that the 

 ciliated bodies produced in this way were " propagative cells of 

 the SpirogyriB capable of development." In the '' Postscript " to 

 my " Observations," however, I expressed a different opinion, 

 having at first, with Professor Pringsheim, been under the im- 

 pression that a development of such " cells " under such circum- 

 stances could only belong to the plant in which it took place, 

 and therefore I called them " gonidia.^^ But subsequent obser- 

 vations favoured the view that they did not belong to Nitelltty 

 and therefore that they should have been called " monads ;" 

 viewing " monads " in the same relation to Infusorial that 

 "gonidia" bear to future Algoid developments. That there is a 

 great resemblance between gonidia and monads, and that there 

 may be instances where their subsequent forms alone can deter- 

 mine which appellation should be used for them, in the sense 

 mentioned, may be easily conceived, and the present is one to 

 the beginner ; but whether or not it should be so to the expe- 

 rienced observer, I will not now stop to discuss. 



Like all unfinished investigations, my first communication 



* Ann. and Mag. Nat. Hist. vol. xvi. No. 91. p. 1, 1855. 

 t Id. vol. xi. No. 64. p. 2.94, 1853. 



