LIVING BRACHIOPODA. 383 



Fig. 4. Kight. half of coelouiic cavity of D. lantcllomt, showing oblique nerve and it.s termination in the posterior occlusor 

 muscle; in this figure the retractor bracliia muscle is turned up to expose course of nerve. 



Fig. 5. Ganglion of posterior occlusor muscle, greatly enlarged, idem. 



Fig. 6. Infra-oesophageal ganglia of T. coreanica. 



Fig. 7. Portion of pallium showing gill ampullae, setae, etc., of G. pyramidata. 



Fig. Id. Natural size of object s'.io.vin.; region from which fig. 7 is drawn. 



Fig. 8 to 11. Color markings of t'.ie pallium of various species of Lingulidae. The setae are purposely omitted in these 



figures except in fig. 9. 



Fig. 8. G. pyramidata. 



Fig. 9. L. lepidula. 



Fig. 10. L. anatina. 



Fig. 11. Lingula, species unknown, from Nagasaki. 



PLATE 03. 



Details of circulation in Glottidia jujrainidata and Linyula It'pidula. Arrows indicate direction of currents. 



Fig. 1 to 7. Glotlidiu. pyramidata. 



Fig. 1. Dorsal view showing main and lateral pallia! sinuses with lacunae, and coelomic and median sinuses. 

 Fig. 2. Portion of pallium showing three rows of gill ampullae. 

 Fig. 3. A single row of gill ampullae, greatly enlarged. 



Figs. 4, 5, and G. Transverse sections through lacune of pallium. Appearance of polygonal cells of endotlielittm. 

 Fig. 7. Showing regions of above sections. 



Fig. 8 to 12. Lingula Icpidula. 



Fig. 8. Dorsal view. The left brachium is shown with cirri removed. 

 Figs. 9 and 10. Opening of main pallial sinus and adjacent parts. 



Fig. 11. A portion of main pallial sinus showing diverltcular lacunae; these appear quite circular in section. 

 Fig. 12. A single lacune, in section, greatly enlarged. In the drawing of Lingula, at one side, is indicated the region 

 from which figs. 11 and 12 were taken. 



Fig. 13. Lateral sinus of G. pyramidata; t'.iis is figured on the plate laterally. 



PLATE 54. 



Circulation, blood corpuscles and uephridia of various forms. 



Fig. 1. Hide view of G. pyramidata, showing result of injection of red fluid through peduncular cavity. 

 Fig. 2. Dorsal view of same. It will be seen that in this experiment the fluid filled the median sinus and the minute 

 vessels of the perivisceral lining, but did not enter the coelouiic cavity or the sinuses of the pallium. 

 Fig. 3. Blood corpuscles of G. pyramidata. 

 Fig. 4. Same of L. lepidula. 

 Fig. 5. Same of L. anatina. 

 Fig. (i. Same of D. lamellosa. 

 Fig. 7. Same of T. coreanica. 

 Fig. 8. Same of 2'. septentrionalix. 

 Fig. '.). Left nephridium of G. pyramidata. 



Fig. 10. Greatly enlarged view of portion of nephrostome, idem. 

 Figs. 11, 12, and 13. Nephrostome of L. lepidula. 

 Fig. 14. Nephrostome from the under side, idem. 

 Fig. 14a. One fold of nephrostome greatly enlarged showing ciliary ridge, idem. 



