214 FRESH- WATER RHIZOPODS OF NORTH AMERICA. 



four, each again successively collapsing. With the appearance of the con- 

 tractile vesicles the contiguous sarcode began to clear up, the brownish 

 matter accumulating below the position of the usual position of the nucleus 

 when present. 



The sarcode of the parent now contracted at the middle, leaving a 

 space between it and the sides of the shell, as seen in fig. 1 7. It afterward 

 became clearer in the vicinity of the mouth, then separated from that of 

 the offspring, and retracted a short distance. Simultaneously the same 

 changes occurred in the offspring. 



At five minutes to 8 o'clock, the two Euglyphas swayed slightly from 

 side to side, protruded one or more delicate pseudopods, and two minutes 

 afterward completely separated, and, with the mouth downward, slowly 

 moved away from each other. 



Half an hour after separation, a pale nucleus was visible in both indi- 

 viduals in the usual position, but the mode of its origin entirely escaped 

 my observation. Two or more contractile vesicles disappeared, and reap- 

 peared around, but rather below, the position of the nucleus. 



While the parent retained the original size, the young Euglypha 

 remained slightly smaller. 



The subject of this observation I have supposed might indicate one of 

 the modes of reproduction of Euglypha, that is to say, the mode by division. 

 As, however, Euglypha is often observed containing within the parent shell 

 an ovum-like body, the process described may indicate the hatching of 

 such a body, with segmentation of its sarcode, and the partition of this 

 between the new and the old shell. 



EUGLYPHA CILIATA. 



Plates XXXV, figs. 19,20; XXXVI; XXXVII, figs. 30, 31, as E. strigosa. 



Difflugia eiliala.* Ehrenberg : Mouatsb. Ak. Wis. Berlin, 1848, 379; Abh. Ak. Wis. Berlin, 1871, Taf. ii, 



Fig. 26.— Leidy : Pr. Ac. Nat, Sc. 1878, 172. 

 Euglypha eomprcssa. Carter: An. Mag. Nat. Hist. 1864, xiii, 32, pi. i, fig. 13. — Leidy: Fr. Ac. Nat. Sc. 



1874, 226.— Schulze : Archiv mik. Anat. 1875, xi, 101, Taf. v, Fig. 3, 4. 

 Setigerella eiliata. Ehrenberg: Abh. Ak. Wis. Berlin, 1871, 247. 

 Difflugia pilosa. Ehrenberg: Ibidem, 256, Taf. ii, Fig. 28. 

 Setigerella pilosa. Ehrenberg: Ibidem, 247. 

 Difflugia strigosa. Ehrenberg: Ibidem, 257, Taf. ii, 31. 

 D. Setigerella strigosa. Ehrenberg : Ibidem, 247. 

 Euglypha strigosa. Leidy : Pr. Ac. Nat. Sc. Phila. 1878, 172. 



* The original description is: " Lorica ovata, superficie areolata, areolis singulis posterioribus cir- 

 rhigeris, osteoli parte attenuata, aperturae denticulis 10-16. Long. — ■} s l ". D. areolatse non cirrhigerae 

 admodum similis." 



