HYDRACHNA. 265 



acre. But the pond being stocked mth perch about that time, the 

 HydrachnfB became rare subsequently. 



They were also very numerous afterwards. I remarked the like in 

 1809. 



About that time, some, of many falling into my possession, survived 

 above a year. 



The history of only a few specimens has been preserved along with 

 this brief narrative, for the purpose of illustrating the general and varied 

 features of a very singular race of living beings. 



Plate LXVIII. 



Fig. 1. Hydrachna cruenta. 



2. The same, enlarged. 



3. Another specimen, natural size. 



4. The same, enlarged. 



5. Limb, enlarged. 



6. Spawn, enlarged. 



7. Young from the same, enlarged. 



8. Spawn o{ ffydrac/ma ferox, enlarged. 



9. Hydrachna extendens. 



10. The same, enlarged, back. 



11. The same, enlarged, belly. 



12. Spawn, natural size. 



13. The same, enlarged. 



14. Other spawn of the same, enlarged. 



15. Young from fig. 14, enlarged. 



16. Group of young from fig. 12, enlarged. 



17. Empty spawn, the young having been discharged. 



18. Portion of the same, enlarged. 



19. Hydraclma geograpMca. 



20. The same, enlarged. 



21. Hydrachna caudata. 



22. The same, enlarged. 



23. Spawn of Hydrachna sparsa. 



24. The same, enlarged. 



25. Hydrachna punctata. 



26. The same, enlarged. 



2 L 



