248 Miacellan&ms. 



a degree of differentiation in esse as marked as that which we recog- 

 nize as potential in the earliest stage of the vertebrate embryo. In 

 the former the organization is present, but not circumscribed into 

 regions ; in the latter it is also present uncircumscribed, but it is to 

 be eventuaUy differentiated. The Sponges, with their supposed slimy 

 protoplasm-Hke simplicity, have been in former years the hunting- 

 ground of the developmentalists ; but of late that group has been 

 slipping out from under the feet of those philosophers. 



Carter first detected the true criterion of their animality, thougli 

 erring as to their classificatory relationship. It was my good for- 

 tune to prove their close alliance with the FJageJlata, in a memoir 

 (Mem. Boston Soc. Kat. Hist. vol. i. pt. 3, Sept. 1867, " On the 

 Spongise ciUatae as Infusoria flagellata "*), published some few years 

 ago. I described certain monad-like infusoria which possessed 

 a single Jiigellum surrounded by a projecting membranous collar. 

 Some forms were appended to branching stems {Codosiga), and others 

 w'ere ensheathed in a funnel-shaped or urnaeform tube {Sal jiing fern). 

 The monadiform body of these I showed to be identical with the 

 ciliate bodies of one of the Spongise ciliatso (Lencosohninj), and ho- 

 mologized the branching stem and the ensheathing tubes of the 

 former with the gelatinous mass of the latter, in which its monads 

 were imbedded. The connexion seemed not even a step wide, so 

 clear and unmistakable was the relationship. That there should 

 ever be chscovered a form which would lie so intermediate between 

 these as to make me hesitate whether it belonged to the one or the 

 other, I did not even hope for ; but it has come unexpectedlj'. In 

 Schultze's ' A^chi^' fiir mikroskoplsche Anatomic ' (Bd. vi. 4, 1870) 

 Cienkowsky describes, under the name of Phalansterium, a genus 

 which consists of monad-like bodies with a Jiagellum and a project- 

 ing collar like those of Codosiga, Sulpingceca, and Leucosolenia. Of 

 the two species which he illustrates, one (P. consociatum) has monads 

 enveloped in a broad funnel-shaped slimy sheath ; and these sheaths 

 are closely packed side by side, radiatingly, so as to form a shield- 

 like or a hemispherical mass. This comes nearest to the SaJpingceca. 

 The other species (P. intestinum) possesses similar monads ; but they 

 are imbedded basally in a gelatinous intestiniform mass of slime 

 (ScJihim), "with their vibrating lashes extending in every direction" 

 about the cyhndrical colony. Originally each monad is endowed 

 with a separate sHme-sheath ; but eventually these are aU fused 

 together into one common mass. Beyond this, to make a true 

 sponge, we need but the presence of spicula, and open interspaces 

 in the slimy mass between the monads leading to one common 

 cavity. Introvert the layer of monads, and w^e produce the desired 

 effect without doing violence to their relative positions. It is a mere 

 matter of proportions, just as the inverted cyathiform rose-hip is 

 none the less an ovariferous disk than the globular receptacle of tlie 

 strawberry. — SilUman's American Journal, Feb. 1871. 



• 'Annals,' 1868, vol. i. p. 133 &c. 



