630 DK. II. CHAELTON BASTIAN ON THE ANATOMY AND PHYSIOLOaT 



and the compression of the alimentary canal with complete obliteration of its 

 cavity. 



Fig. 5, Transverse section of one of lateral bands, with neighbouring muscle-cells and 

 integument of Ascaris lumlricoides f" from the anterior extremity: — c, ex- 

 ternal chitinous layer with transverse markings ; b, thick homogeneous layer 

 devoid of marking; c and d, layers with oblique markings in opposite 

 directions; <?, internal chitinous layer Avith very delicate longitudinal mark- 

 ings; /, cellulo-granular layer of integument; (/, loose fibrous membrane 

 forming internal boundary of this ; h, one of nucleated cells found in this 

 layer ; i, fibrous framework met with in the anterior portion of lateral bands ; 

 k, transverse section of axial duct or vessel; /, contractile tissue of muscle- 

 . cell; m, contained granular medullary substance; n, section through the 

 central part of a small muscle-cell, showing the mode of origin of the blad- 

 der-like appendages. 



Fig. 6. A portion of one of the lateral ducts removed from the lateral band: — a, its 

 lumen ; b, b, adhering nucleated cells of the lateral band. 



Fig. 7. A portion of the integument seen from the inner surface, the body of the animal 

 having been slit open and the muscles removed: — a, right lateral band; 

 b, its axial duct ; c, c, median lines ; d and e, a pair of delicate vessels run- 

 running through the cellulo-granular layer of integument from median line to 

 median line, and crossing one another in the substance of lateral band. 



Fig. 8. One of muscle-cells, lateral aspect : — a, contractile portion ; b, bladder-like deve- 



- lopment; c, transverse muscular prolongations; d, nucleus of muscle-cell; 



e, superficial granular material, sometimes containing delicate cells. 



Fig. 9. A more elongated muscle-cell, with no bladder-like development seen, but a 

 stronger transverse prolongation. 



Fig. 10. Showing the constitution of intestinal wall : — a, extemal structureless mem- 

 brane ; b, b, two columnar hepatic cells ; c, very thin internal structureless 

 layer, perhaps formed by a thickening of the cell-wall at this part. 



Fig. 11. Tessellated appearance presented by extremities of hepatic cells. 



Fig. 12. Floating cells from the general cavity of body of Ascaris lumbricoides. 



Fig. 13. External transverse markings of the integument of same. 



Fig. 14. Portions of the two sets of lamellae with oblique markings. 



Fig. 15. Internal chitinous layer with very fine longitudinal mai-kings. 



Fig. 16. Section through anterior part of one of lateral bands and adjacent integument 

 of Ascaris megalocephala ; references same as in fig. 5. The principal differ- 

 ences are that the band is here absolutely smaller, and the vessel absolutely 

 larger ; whilst no fibrous framework exists in the band, whose complete con- 

 tinuity with the deep integumental layer may be well seen. 



