ON DtPLOZOON NIPPON ICUM, N. SP. 159 



sits on a basement membrane An embryolog-ical stncl}', however, 

 of the transformations which the original epidermis undergoes is. as 

 Braun maintains, very desirable. 



The integument of Dipl, nippouicum is comj)Osed of two layers, 

 the cuticula and the underlying matrix. The cuticuLi, when 

 examined in a living worm, is a very thin, structureless, refractive 

 membrane. In sections of hardened specimens it appears as an 

 insignificant line bonnding the subcuticular (= epidermal) layer 

 against the external world. It is very well seen in a living specimen 

 wliich has been nllowed to macerate in water for some time under 

 the cover-glass. Numerous watery blisters then form in the epider- 

 mis, and separate the cuticula from the underlying layer. The 

 former cnn then be examined as a separate structure. Transverse 

 canals have been described in the cuticula of many Trematodes, but 

 I have not observed any in the new species. The cuticula is reflected 

 inward for some distance into the mouth. 



Directly luider the cuticula lies the epidermal layer, a uniform, 

 granular matrix in which no nuclei are to be observed. I believe 

 I have observed indistinct dark Hues traversing the breadth of this 

 Liyer but not quite reaching the cuticula. The epidermal layer, like 

 the cuticula, is continued into the cavity of the mouth, and the sticky 

 glands hereafter to be described (p. 166) are but local modifications 

 of it. Wierzejski'^ describes the "Haut" of Calicotyle Kroyeri as 

 consisting of " einer feinen Cuticularschicht mit den darunter liegenden 

 kleinen, runden Matrixzellen "; but judging from his figure, I beheve 

 he has mistaken the imclei of the connective tissue for his " Matrix- 

 zellen." The epidermal layer rests on a basement membrane, which 

 eagerly takes up coloring matter, and is very conspicuous in cross- 



1) VVierzejski— Zur Keantaiss des Baues von Calicotyle Kroyeri. Ztschr. f. wiss. Zool. 

 Bd. XXIX. 1877. p. 552. 



