Mr. R. Q. Coiic'h on the Morphohgy of Zoophjtes, 161 



XXII. — On the Morphology of the different Organs of Zoophytes, 

 By R. Q. Couch, M.R.C.S.L * 



[With a Plate.] 



The subject which I have to bring under the notice of the So- 

 ciety today is, if it proves true, one of great beauty and unusual 

 interest, inasmuch as the lowest forms of animal life will in the 

 development be found to be governed by the same laws that 

 govern the growth of flowering plants. The vegetable law to 

 which I refer is the metamorphosis of the leaf into the various 

 organs which constitute the perfect plant. This law is now so 

 well established and so generally allowed that nothing is required 

 to be said of it ; on the present occasion I shall therefoi^ proceed 

 to discuss its application to the animal kingdom. To Professor 

 E. Forbes belongs the merit of first promulgating the theory of 

 the morphology of the reproductive system of the Sertularian 

 Zoophytes and its analogy with the reproductive organs of flow- 

 ering plants. This he did at the late meeting of the British As- 

 sociation held at Yorkf. It is an opinion I have long enter- 

 tained, and in elucidation of which I have for some time been 

 examining almost all the species found on our shores. The views 

 were so new that I hesitated to adopt them, and had I not found 

 that they were held and published by others, I should not now 

 have brought them before this meeting. I do so to show how far 

 the theory of Professor E. Forbes is supported by inductive ob- 

 servations ; and that though we pursued in a great measure dif- 

 ferent paths, we yet arrived at similar conclusions. As Professor 

 Forbes confined his observations to the genera Sertularia and 

 Plumularia, they are the ones which will be referred to here, 

 though the same observations may be extended to several genera 

 of the Ascidian Zoophytes ; Crisia and Cellularia for instance. In 

 making these observations I shall refer to their growth ab ovo, and 

 trace the different parts through their development to the fully 

 formed character. These creatures resemble plants in their ar- 

 borescent appearance, rooted character, and the transient nature 

 of their reproductive organs. The Sertularian genera have an 

 external horny, elastic and irritable sheath, and this incloses a 

 central granular pulp which extends into all the ramifications and 

 from which all the other parts are formed. On the branches are 

 numerous variously shaped and variously arranged cup-like cells ; 

 but their arrangement and shape are always alike in the same, 

 but difi'erent in different species. These are the polype cells, in 



* Read before the Natural History Society of Penzance, Dec. 3, 1 844, and 

 communicated by the author. 



t As reported in the Athenaeum. The entire paper, illustrated by a plate, 

 was inserted in our Number for December 1844. 



Ann. ^ Mag. N. Hist. Vol. xv. N 



