GLOSSARY OF TECHNICAL TERMS. 867 



Cuirass. Fr. from adr, leather. An indurated defensive shield, synonymous with 

 Carapace. 



CUTICULUM. Lat. cuticula, a little skin. The more indurated pellicle which forms the 

 outer layer of the body of Infusoria. 



Cyclosis. Gr. kuklosis, a moving round. The protoplasmic circulation observable in 

 the cells of certain plants, and also in many Protozoic organisms such as within the 

 body of Paramecium bursaria and the pseudopodia of the Foraminifera. 



Cytoblastema. Gr. kutos, a cell ; blasia7io, I bud. The viscid fluid in which animal 

 and vegetable cells are produced. Here applied to the glairy structureless matrix in 

 which the collared and amoebiform cells of the sponge-body are immersed and 

 generated. 



Cytoblasts. Gr. kutos, a cell ; blastaiw^ I bud. The amoebiform cells immersed and 



generated within the hyaline matrix or cytoblastema of a sponge-body. 

 Cytodes. Gr. kutos, a cell. A term applied by Haeckel to unicellular organisms or 



elements, that have the value of a simple cell but possess no distinct nucleus. 

 Cytopyge. Gr. kutos, cell ; puge, the rump. A term introduced by Haeckel for the 



distinction of the so-called excretory or anal aperture of unicellular animals. 

 Cytostome. Gr. kutos, cell ; stoma, a mouth. A term proposed by Haeckel for the dis- 

 tinction of the so-called oral aperture of unicellular animals. 

 Dactylozooids. Gr. daktulos, a finger ; zoon, animal. Term proposed by H. N. 



Mosely for the distinction of the attenuate mouthless zooids developed by Millepora, 



Stylaster, and other coral-building Hydrozoa. 

 Diaphanous. Gr. dia, through ; phaino, I show. Transparent, permitting the passage 



of light. 

 Diastole. Gr. diastello, to dilate. A term expressive of the expanding action of the 



contractile vesicle of Infusoria and other Protozoa. 

 DIATOMIN. Gr. diatemno, to separate. A term applied to the essential brown colouring 



matter of the vegetable organisms known as Diatoms. 

 DiCHOTOMOUS. Gr. dicJia, in two parts ; toine, a cutting. Having the divisions of its 



substance arranged in pairs ; furcate or forked. 

 Decurrent. Lat. de, down ; cur reus, running. Running out or projecting beyond. 

 Differentiated. Lat. differo, I separate. Applied to an organic body or structure 



which exhibits a distinct separation into diverse elementary components. 

 DifflueNCE. Lat. diffluefis, dissolving. A term introduced by Dujardin to indicate that 



pecuhar phenomenon of dissolution exhibited by many Infusoria, in which the sarcode 



substance of their bodies as it were gradually melts away. 

 DiCECiOUS. Gr. dis, double ; oikos, a house. Having the male and female sexes repre- 

 sented in two distinct individuals. 

 DiPLOBLASTIC. Gr. diploos, double ; blastos, germ. Relating to that condition of the 



Metazoic embryo in which two germinal cellular layers are distinctly represented. 

 Dextrogyrous. Lat, dextra, the right hand ; gyros, a circle. Circling towards the 



right. 

 Dextrotropous. Lat. dexter, to the right ; Gr. trope, a turning. Turning to the 



right. 

 ECTODERM. Gr. ektos, outside ; derma, skin. The external of the two germinal cellular 



layers, common to all multicellular or Metazoic animal organisms, out of which are 



developed the protective and sensory elements, including the skin, cuticle, nervous 



system, and organs of special sense. 



ECTOPARASITIC. Gr. ektos, outside ; parasitos, parasite. Having the nature of an 



external parasite. 



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