[ 19 ] 
IV. Further Observations on the Manatee. By James Morin, W.D., LL.D., F.G.S., 
Assist. Secretary Linnean Society. 
Received June 17th, read June 17th, 1879. 
[Puates V.-IX.] 
ConTENTS. 
Review of recent Researches on Manatus . page 19 On the Cervical Nerves . . . . . « page dd 
History and Observations on Habits of Live Spe- OnetheeBrainy | oa tates xa peter ene omer aU, 
cimen .. Y 5 Al Concluding Remarks . . ....... 42 
Notes on Dead Specimen, its outward aspect . 27 Description of the Plates. . . . . . . . 45 
Memoranda on the Muscular System . . . . 32 
REVIEW of recent Researches on Manatus.—Since the publication in the Society’s 
‘ Transactions’ (vol. viii. pp. 127-202) of my researches “On the Form and Structure 
of the Manatee,” three important papers on the development and anatomy of this 
animal have appeared !. 
1. In the American ‘ Journal of Science and Arts,’ vol. x. Aug. 18757, Prof. Burt G. 
Wilder, of Cornell University, has writen a short but trenchant article, with a plate, 
“On a Fetal Manatee and Cetacean, with Remarks upon the Affinities and Ancestry 
1 In the above remarks on the literature I haye solely restricted myself to anatomical labours on the Manatee. 
Short notices, such as those by Dr. Sclater (P. Z. 8. 1875, p.529), Prof. Garrod (P. Z. 8. 1875, 529 & 567), W. 
B. Tegetmeier (‘ Field, July 6, 1878), and E. Harting (‘ Zoologist,’ 1878, p. 285), need no more than passing 
mention. I should, though, do injustice to two writers did I remain silent respecting their papers, viz. :— 
1. “On the Affinities of the Sirenians,” by Dr. Theodore Gill (Proc. Acad. Nat. Sci. Philadelphia, 1873, 
pp- 262-273). In this cleverly put dissertation the author suggests ‘that the ordinary Cetaceans and the 
Sirenians are derivatives from a common original stock—a generalized Gyrencephalic type.” He admits we 
haye no clear evidence of such a progenitor. Afterwards he discusses the relations of the Sirenians, analyzing 
the characters, differentiating Manatus from Cetaceans, and, again, those characters common to the Sirenia and 
Ungulata, of which latter he allows there are none. Neither does he admit Manatus among the Pachyderms. 
Lastly he deduces the genealogy of the Sirenia thus :—Proto-Sirenian, whence Halitheriide, Halicoride, and 
Rhytinide on the one hand, and the Trichechoidea on the other. 
2. “ Description de l’Ciuf et du Placenta de Halicore dugong,” par le Dr. Paul Harting (Tijdsch. d. Nederl. 
Dierk. Vereen, Deel iv. 1879, pp. 1-29, pls.i., ii.). Most interesting, no Sirenian placenta haying hitherto been 
examined. This research is based on a foctus and membranes in the Zoological Museum of Utrecht. A full 
description of the structural peculiarities is given, showing it to be a diffuse, non-deciduous placenta; and 
then follows a comparison with that of Cetacea and divers Pachyderms, between which groups it seems to 
stand midway. The author acknowledges that the diffuse form of placentation is met with in groups so much 
apart that its taxonomic significance loses all value; even the distinction deciduous and non-deciduous, in his 
opinion, cannot lead to a natural classification. 
2 Pp. 1-10, plate viii. I here quote from a separate copy extracted from the Journal in question, and 
kindly forwarded me by the author. 
VoL. X1.—PART U1. No. 1.—August, EOD E 
<\Sh, Mus 
Sp F- 2 Gn 
iy 
x 
eS 
Gat wis 
