TEREBELLA. 203 



within an internal organ of a different specimen from any of the preced- 

 ing, but not accumulated in an ovarium. On the contrary, they were 

 loose, rising and falling within the cavity like small shot dropped amidst 

 a very dense and resisting medium. This continued several weeks with- 

 out any definite consequence. 



It might have been some architectural materials for the tube. 



Were many alike prolifice as the most fertile above quoted, the race 

 should be common. But in districts where the other Terebellae abound, 

 this species is on the contrary rare. Thus I have either never found the 

 place of its nativity, or, surrounded by enemies, the most of the progeny 

 perish at an early stage. Observers are prone to conclude that the repro- 

 ductive faculties are lavished in superfluity on the lower animals ; that the 

 embryonic members are excessive, so that the world would be incapable 

 of sustaining the whole did they reach maturity, or even on advancing a 

 short way in progress towards it. Shall we, therefore, deem it essential 

 to the harmony of the universe, that exposure to danger shall admit de- 

 struction of the young, while only a few adults are preserved to fulfil the 

 general laws of Nature ? 



Specimens have survived nine months in confinement. 



PLATE XXVIII. 



FIG. 3. Terebella concMlega. 



4. Extremity enlarged. 



5. Branchiae, natural size. 



6. Tentaculum conveying a portion of shell, a, enlarged. 



7. Tentaculum, shewing the spots on the back, enlarged. 



8. Ova. 



9. Ova, enlarged. 



5. TEREBELLA MACULATA The Spotted Terebella. Plate XXVII. 



Figs. 10, 11, 12, 13. 



Compared with any of the preceding species, the subject of this 

 paragraph is one of the smaller Terebellae. Its length is disproportionately 



