4G Mr. K. Vallentin on the 



LacinuJarm socidis, I nt last siicoeeded in obtainliiGj one 

 scries of sections that left no doubt on my own mind as to 

 the fiiiul termination of the lateral canals. On reference to 

 fig. 13 the thin membranous-like termination of the united 

 lateral canals will at once be seen. The slightly dilated 

 junction rapidly narrows and opens to the exterior immedi- 

 ately beneatli tlie anal aperture (fig. 13, e). I think the 

 extreme difficulty one experiences in viewing in a satisfactory 

 manner the termination of these lateral canals is mainly 

 owing to the extreme delicacy of the walls of the lateral 

 canals in the region of the posterior third to their junction. 

 This statement receives confirmation from the fact that the 

 termination of the lateral canals in all my other sections has 

 eluded my most careful scrutiny. 



LiTEUATUUE REFERRED TO. 



(1) Hudson, C. T., and Gossk, P. II. The Rotifera or Wheel- 

 aDimalcules. 188G. 



(2) JoLiET. " Monog-raphio des Meliceries," Arch, de Zool. exper. et 



gen. vol. i. 188-'j. 



(.3) Huxley, T. H. " Lacinularia socialis : a Contribution to tho 

 Anatomy and Physiology of the Kotifera,'" Trans. Micr. 8oc. Lond. 

 vol. i. 1853. 



(4) Lrydig, F. " Zur Anatomic und Kntwicl<lung.«gepchichte dtr 

 Lacinularia socialis,^'' Zeit.schr. f, wiss. Zool. iii. 1851. 



(5) Williamson, W. C. " On the Anatomy of Melicerta riiit/e)i.-<," 

 Quart. Journ. Micr. Sci. vol. i. 185.3. 



(G) OossR, P. II. " On the Structure Functions, Habits, and Deve- 

 lopment of Melicerta ritif/enn,'" (Juavt. Jouni. Micr. Sci. vliI. i. 

 1853. 



(7) . " On tlie Structure, Functions, and Homologies of tlie 



Manducatory Organs in tlie Class Kotifera," Pliil. Trans. 1S55. 



EXPLANATION OF Till-] PLATES. 



List of Reference Letters. 



I.e. Lateral canals. ST., st. Stomach. 



o. Ovarj'. f. Intestine. 



s.(j. Salivary glands. c. Cuticle. 



S.lv. Salivary receptacles. yj. Gastric glands. 



a. Opening of salivary receptacles !r. Opening of gastric glands into 



nito pharynx. a'sophagus. 



//. Ganglia (brain). «>. (Iv-;opliagus. 



»(. Mu.^^clcs. b.c. liody-cavitv. 



m.c. Mucous cell.<^. f.c, Flanie-ccll." 



