108 BIOLOGICAL SURVEY OF 



Geographical distribution. Portland, Maine (Dawson) ; 

 Gulf of St. Lawrence (Lambe), Mount Desert Region. 



SuBERiTES MONTALBiDus Carter 



Lambe (1895, p. 127, pi. 3, figs. 6, 6a-c). 



Several fragments representing probably 2 or 3 individuals 

 of this species were taken at Station 107, on rock, depth 165 

 feet. 



Skeleton. This is composed of large tylostyli irregularly 

 intermixed. The dermal skeleton is composed of two forms 

 of small spicules and distinct bundles of small tylostyli placed 

 at right angles to the surface and projecting slightly beyond 

 it. The small inflated spicules are also scattered throughout 

 the interior of the sponge. 



Spicules. 1) Tylostyli as well as some subtylostyli vary in 

 length from .324 mm. to .405 mm., with a mode at .364 mm. 

 These spicules may be straight or curved and frequently have 

 small secondary inflations near the head end. Lambe does 

 not record the presence of any subtylostyli, although Carter 

 (1880, p. 256) in the original description describes the head as 

 'variable in shape.' 2) A few small oxeote spicules, inflated 

 at their midlengths, are found and these vary from .041 mm. 

 to .052 mm. in length. Lambe found these spicules to be 

 minutely spined, but there is no evidence of spination in the 

 specimens of this region. Carter makes no mention of their 

 being spined in the original description. 3) Small, straight 

 or curved, cylindrical spicules, with rounded ends and inflated 

 at or near the midlength of the shaft, are present in large 

 numbers. These are always smaller than the oxeote spicules 

 and vary from .013 mm. to .028 mm. in length. Lambe re- 

 cords these spicules as minutely spined also, but there is no 

 evidence of spination in these specimens. 



Remarks. Siiberites montalhidus is readily distinguished 

 from the other species of Suherites which are found in this 

 region by the presence of the small inflato-spicules. It is 

 distinguished from Suherites ficus, which has been reported 

 from the Gulf of St. Lawrence but never taken in this region, 

 by the presence of the small inflated oxeote spicules. 



