Zoolog;/.'] NATURAL HISTORY OF VICTORIA. [Polyzoa. 



Plate m, Fig. 1. 

 DICTYOPORA GRISEA (Lamx.). 



[Genus DICTYOPORA (P. McG.). (Sub-kingd. Mollusca. Class Polyzoa. Order 

 Infundibulata. Sub-order Cheilostomata. Fam. EscharidEe.) 



Gen. Char. — Polyzoary, stony, expanded, foliaceous, fenestrate, articulated by a flexible 

 stem ; cells horizontal, opening on both sides ; a special pore on the front of each, close to 

 which is an avicularium.] 



Description. — Polyzoary fan-shaped, flat, occasionally proliferous ; fenestras 

 large, nearly circular, the marginal rim divided into distinct pitted nodules ; cells 

 rounded above, attenuated below ; mouth rather small, circular or nearly so, the 

 margin somewhat thickened ; a wart-like projection below and to one side of the 

 mouth ; surface, except on the summit of the elevation, pitted ; a round pore 

 near the middle of the cell, close to which is an avicularium of moderate size, the 

 triangular mandible turned obliquely outwards to the side opposite the wart-like 

 projection. 



Keferences. — Adeona grisea, Lamouroux, Exposition Methodique, p. 40, t. 70, 

 fig. 5 ; Kirchenpauer, Ueber die Bryozoen-Gattung Adeona, p. 9, t. I., fig. 8, 8cf. 



Port Phillip Heads. 



Of this species I have examined two perfect specimens, the one 

 figm-ed, dredged by Mr. Wilson, and the other by myself, in about 

 12 fathoms. In both the frond or plate is quite flat, not being 

 twisted or contorted in any way, and extends more to one side of 

 the stem. In the figured specimen it is 3|^ by 2f inches, and in 

 the other 4 by 3. The flexible stem in one is 1 inch by fths at 

 the widest part, in the other about IJ by Jth. In both it termi- 

 nates in a number of small radicles presenting the same structure 

 as the main stem, by which they are fixed to the calcareous 

 nodules on which they are growing. Raised branching processes 

 or ribs extend for a considerable distance up the plate. The 

 fenestrse are regularly placed, nearly circular or elliptical, 2-3 mm. 

 in diameter, the intervening spaces 3-5 mm. The margins of the 

 fenestrse, as in D. cellulosa, are divided into nodules resembling 

 abortive cells. 



D. grisea may be distinguished fi'om D. cellulosa., to which in 

 the structure of the cells it is closely allied, by the simple flabellate 

 frond (said by Kirchenpauer to be sometimes proliferous), by the 

 avicularium being shorter and directed obliquely across the front 



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