. The crayfish : An introd. to the study of zoology. --. Crayfish; Zoology. 136 THE PHYSIOLOGY OF THE COMMON CRAYFISH. of what occurs in other animals, however, leaves no doubt that an actual mixture of the male and female ele- ments takes place and constitutes the essential part of the process of impregnation. Ova to which spermatozoa have had no access, give rise to no progeny; but, in the impregnated ovum, the young crayfish takes its origin in a manner to be described below, when the question of development is dealt Fig. 35.—Astacus fluviatilis.—The last thoracic sternum, seen from
. The crayfish : An introd. to the study of zoology. --. Crayfish; Zoology. 136 THE PHYSIOLOGY OF THE COMMON CRAYFISH. of what occurs in other animals, however, leaves no doubt that an actual mixture of the male and female ele- ments takes place and constitutes the essential part of the process of impregnation. Ova to which spermatozoa have had no access, give rise to no progeny; but, in the impregnated ovum, the young crayfish takes its origin in a manner to be described below, when the question of development is dealt Fig. 35.—Astacus fluviatilis.—The last thoracic sternum, seen from behind, with the proximal ends of the appendages, A, in the male, B, in the female, ( x 3). am, articular membrane ; cxp, coxopo- dite ; st XIV, last thoraoic sternum ; vd, aperture of vas Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Huxley, Thomas Henry, 1825-1895. London : K. Paul, Trench, Trubner
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1896
