Tedania gurjanovae — Baku s 
59 
Fig. 1. Tedania gurjanovae Koltun (X 2 A) ■ Small sample, Specimen No. 58. Large 
sample, Specimen No. 112, encrusting on Modiolus. 
throughout the endosome. Onychaetes (Fig. 2c- 
e) occur both scattered and in trichodragmata. 
Excurrent canals measure up to 500 fx in diame- 
ter, whereas smaller canals range down to 83 ^ 
in diameter. Canals are moderately numerous. 
The spicules and their dimensions are listed 
in Table 1. The mean dimensions of each spicule 
category of specimen No. 30 and 112 are based 
on 10 measurements, and each size range is 
represented by 1 minimum and 1 maximum 
measurement. 
The styles are often curved. Occasional ju- 
venile styles were observed. Hastate tornotes 
sometimes have very slightly inflated ends. 
Onychaetes are straight or slightly curved and 
occur in two size ranges. The smaller forms ( I ) 
tend to be prominently roughened, whereas the 
larger sizes (II) are only slightly rugose (Fig. 
2 c-e). Juvenile onychaetes also occur. One 
measurement is 81 X 1 g-. Onchaetes are often 
found in trichodragmata measuring from 60 to 
100 fx thick. 
ECOLOGICAL NOTES 
Tedania gurjanovae is collected chiefly from 
a biotic community of lamellibranchs (mussels) 
and barnacles. In some specimens the endosome 
is contaminated by a few sand grains. 
Biological associates include: No. 30, T. 
gurjanovae partly encrusting on barnacles ( Bala- 
nus ) with another sponge (Halichondria) , all 
of which are encrusting on the carapace of a 
crab; No. 58, T. gurjanovae encrusting around 
a barnacle ( Balanus ) with attached polychaete 
tubes ( Fig. 1 ) ; No. 90, T. gmjanovae encrust- 
ing on barnacles {Balanus) ; No. 112, a few 
foraminifera on the sponge surface, T. gurjano- 
vae encrusting on a mussel {Modiolus modiolus 
Linnaeus) and surrounding a barnacle {Balanus) 
and several large polychaete tubes (Fig. 1); 
No. 163, one large endosomal polychaete tube. 
Koltun (1959:156) reported that Tedania gur- 
janovae is frequently found encrusting on the 
valves of scallops ( Chlamis ) . 
