NO. 15 SPONGES DE LAUBENFELS 3 



inequiended strongyles. The endosomal spicules vary from en- 

 tirely spined to spined only on the heads. All the spicules are 

 much larger than in roosevelti. 



b. Merriamium buchani was described as Lissodendoryx b. by Top- 



sent, 1913, p. 626, from the Antarctic. The ectosomal spicules 

 are tylotes. The endosomal spicules are only rarely tuberculate, 

 and all the spicules are much larger than in roosevelti. 



c. Merriamium certum was described as Dendoryx c. by Topsent, 



1892, p. 99, from the North Atlantic. The ectosomal spicules 

 are hastate tornotes. The endosomal spicules are acanthostyles 

 (not tylote) and both sorts are much larger than in roosevelti. 

 The microscleres are two sizes of arcuate isochelas, very dif- 

 ferent in shape from those of roosevelti. 



d. Merriamium clavigerum was described as Esperella c. by Levinson, 



1886, p. 360, from the Arctic. The ectosomal spicules are 

 oxeas nearly three times as large as the ectosomal tylotes of 

 roosevelti. The other spicules are more nearly like those of 

 roosevelti than is true of most species in the genus, but differ 

 in many little details of shape. 



e. Merriamium kymum was described as Lissodendoryx k. by de 



Laubenfels, 1930, p. 27, from California. Both the ectosomal 

 spicules and the microscleres are somewhat like those of roose- 

 velti, but the endosomal spicules are about twice as thick and 

 more than twice as long, and are mostly smooth ; only an occa- 

 sional one has a few scattered spines. 



/. Merriamium lindgreni was described as Dendoryx mollis by Lind- 

 gren, 1897, p. 482, and given the new name lindgreni by de 

 Laubenfels, 1936, p. 83, because there was already another 

 Dendoryx mollis. It is an East Indian species. The ectosomal 

 spicules are much like those of roosevelti, but the endosomal 

 spicules are nearly twice as long, but not thicker, and lack the 

 tylote modification. The microscleres are much larger and of a 

 different shape than those of roosevelti. 



g. Merriamium lobosum was described as Lissodendoryx I. by Lund- 

 beck, 1905, p. 154, from the Arctic. All the spicules are much 

 as in M. lindgreni, but the microscleres differ radically in shape 

 from those of all others of the genus. 



h. Merriamium lundbecki was described as Lissodendoryx I. by Top- 

 sent, 191 3, p. 41, from the North Atlantic. The spicules are 

 much like those of M. clavigerum (d, above) but the endosomal 



