402 REPORT—1869. 
In certain other naked-eyed medusz, such as those belonging to the genus 
Thaumantias, Esch., the trophosome of which has been in one species de- 
tected by Wright, and the genera Tiaropsis, Agass., and Tima, Esch., 
which, like Aglaura, have not yet been traced to a hydroid trophosome, the 
reproductive buds are situated, as in Obelia, upon the radiating canals; but 
they occupy with their extended base a much greater length of these canals 
than the corresponding buds in Obelia, Campanularia, or Aglaura do. They 
possess thus a less defined and individualized appearance than in the last- 
named meduse ; but, notwithstanding this, they are constructed upon essen- 
tially the same plan, and afford no exception to the view here taken. 
In Tima, indeed, we have an extreme case of this extension of the base of 
the generative buds, which here present themselves in the form of four long, 
Fig. 19.—Portion of the reproductive band in a female medusa of 
Tima Bairdii. 
aa @, radiating canal; bbb, reproductive band; ¢, ectoderm; d, endoderm ; e, cavity 
of the spadix; ¢' e', distal edge of the flattened spadix seen through the ectodermal layer ; 
J, ova. 
Cotas 7 
flattened, sinuous frill-like bands, each attached by one edge along the whole — 
length of a radiating canal (fig. 19). When a section is made from the free 
to the attached edge of this band, the generative elements are seen to be 
disposed upon each side of a hollow longitudinal septum (e, é). This septum 
consists of a diverticulum of the endoderm of the radiating canal; it admits 
into its interior the fluid which circulates in ‘the radiating canal, and is 
plainly homologous with a laterally extended and flattened spadix ; while the 
Band, 8.10). Leuckart recognizes in the generative sacs of Aglaura the significance of 
true zooids, though he refrains from extending this view to the generative sacs of other 
medusee. 
