298 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 105 



Distribution and ecology: Station 44 yielded the holotype 

 (USNM 11311) and a few other colony fragments without soft or 

 chitinous parts. No other species were growing over them. 



Affinities: This species is similar to Smittia antarctica Waters 

 (1904, pp. 65-66, pi. 4, figs. la-h). It differs from Waters' species 

 chiefly in the location of the avicularium. Waters pictm-es the 

 avicularium a considerable distance away from the orifice, while in 

 S. oblongata the avicularium is close to the peristomial notch — in fact 

 intrudes upon it (pi. 28, C). Also, the interior of the avicularial beak! 

 seems to be different in the two forms. No opening is shown in the 

 apparently flat floor of the beak in Waters' species, while there is a 

 sizable opening and a keeled floor in S. oblongata. A third point of 

 difference is in the number of lateral wall pores. Waters mentions 

 10 pore plates while S. oblongata has 4 or 5. A fourth point of difference 

 is in the shape of the zooecia. Waters' specimens are hexagonal, i 

 while those of the current species are rectangular. This may not be ai 

 very important difference since so little material is available. 



Smittina ordinata (IMacGillivray) 



Plates 29, 30 

 Smittia ordinata MacGillivray, 1895, p. 93, pi. 12, figs. 18, 18a, 19. 



Diagnosis: Zoarium small, encrusting. Zooecial frontal convex, 

 granulated to beaded and punctured by numerous evenly and closely 

 set pores. The short heavy peristome interrupted frontally by a 

 notch that cradles the small oval to almost round oral avicularium. 

 No other avicularia. Mandible spatulate. Up to four transitory 

 spines about the orifice in only the very youngest zoids. Secondary 

 orifice clithridiate. Primary orifice with weak lyrula and cardelles. 

 Globose granulated ovicell, punctured by a pore near the midregion 

 (and an occasional peripheral pore), but pores may be obliterated by 

 advancing calcification, which also flattens the ovicells, and the 

 frontal. 



Measurements: Minimum to maximum and average measure- 

 ments, in millimeters, are given below (for explanation see p. 271). 



Z-L, 0.547-0.893 (0.668) Ov-L, 0.230-0.259 (0.249) 



Z-W, 0.353-0.504 (0.388) Ov-W, 0.259-0.288 (0.271) 



Av-L, 0.058-0.086 (0.075) Op-L, 0.092-0.096 (two readings) 



Av-W, 0.046-0.058 (0.056) Op-W, 0.138-0.173 (two readings) 



Pr-Or-L, 0.086-0.101 (0.095) M-L, 0.036-0.055 (0.050) 



Pr-Or-W, 0.137-0.147 (0.142) M-W, 0.036-0.050 (0.043) 



Se-Or-L, 0.144-0.173 (0.153) CS-L, 0.317-0.374 (0.340) 



Se-Or-W, 0.122-0.144 (0.137) CS-W, 0.295-0.432 (0.356) 



Ly-L, 0.022-0.029 (0.023) OS-L, 0.216 



Ly-W, 0.043-0.072 (0.054) OS-T, 0.014 



