2 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 121 



In December and January of 1966-67, I observed an even more 

 impressive mass development of Loxosomella in Church Bay, Har- 

 rington Sound, Bermuda. The rocky littoral, with numerous, typical 

 flame-red fire sponges, merged with a slightly sloping silty bottom 

 in about two meters of depth, where a blackish "variety" of a similarly 

 shaped sponge was abundant on lumps of dead coral rock. It later 

 was discovered that these specimens were covered densely with 

 Loxosomella tethyae, new species, also described herein. Between 500 

 and 2500 specimens w^ere counted per cm 2 , totaling about 20,000 per 

 specimen of host sponge. No other sponge species was infested, nor 

 was the same species infested when growing in water shallower than 

 one meter. 



Methods. — Loxosomella bimaculata and L. parguerensis from Puerto 

 Rico were relaxed with magnesium sulfate and then fixed in Bouin's 

 fixative. Loxosomella tethyae from Bermuda could not be relaxed and 

 w T as fixed directly and preserved in 4 percent formalin in sea water 

 or 70 percent alcohol. The specimens in formalin remained in fairly 

 natural shape; the ones in alcohol showed strong shrinkage in girth. 



All measurements were made on specimens stained with Mayer's 

 hemalum and mounted in "Preservaslide." The total length was 

 measured from the edge of the tentacular membrane to the "toe" of 

 the foot; calyx length, from the edge of the tentacular membrane 

 to the lower point of the stomach; stalk length, from the low r er point 

 of the stomach to the "toe"; calyx width (stomach), at the widest 

 part of the stomach; and calyx width (lophophore), at the widest part 

 of the lophophore (edge of tentacular membrane). For histological 

 sections, a celloidin-paraffin technique was used as described by 

 Antonius (1965). 



Acknowledgment. — I wish to thank Dr. Paul R. Burkholder, 

 Lamont Geological Observatory of Columbia University, N.Y., who 

 provided funds that made collections of these specimens possible. 



Loxosomella bimaculata, new species 



Figures 1-3 



Holotype.— USNM 11928 (slide mount). 



Paratypes.— USNM 11929, USNM 11930 (slide mounts), USNM 

 11931 (alcohol). 



Locality.' — Together with L. parguerensis, new species, on one 

 specimen of fire sponge (Tedania ignis) from pilings (just below low 

 tide level) of the south dock on Maguey ez Island, off La Parguera, 

 Puerto Rico. Collected Apr. 7, 1967. 



Description. — Hundreds of small specimens covered the surface 

 of the host sponge with a density of between 200 and 900 specimens 



