108 U.S. NATIONAL MUSEUM BULLETIN 2 72 



species H. baileyi. Even though some of Schroder's "varieties," in 

 particular the Carterius stepanowii complex, can no longer be retained 

 as races of H. baileyi, H. repens most certainly does not possess distinct 

 morphological criteria to justify its specific separation. 



Although Old (1932b, p. 449) considered H. repens "sufficiently 

 distinct from H. baileyi to stand alone," he failed to demonstrate any 

 particular reasons for his opinion. Morphometric comparisons of a 

 wide range of material of H. repens with the type sHdes of H. baileyi 

 during the present studies did not reveal any marked differences 

 between the spicular components; the megascleres and the micro- 

 scleres were indistinguishable. Some shght differences occur in the 

 spininess of both classes of gemmoscleres, which in H. repens usually 

 is somewhat subdued, whereas in H. baileyi these spines are rather 

 more abundant and larger. However, in a wide range of H. repens 

 such apparent characteristics are by no means constant, and gemmo- 

 scleres intermediate between those described as typical can be found 

 in both these species discussed. 



The futihty of retaining H. repens as a distinct species has thus 

 become obvious, and the present authors have no hesitation in 

 relegating it to a synonym of H. baileyi, which has precedence of 

 many years. Only future detailed studies will be able to decide whether 

 some obvious though immaterial morphometric differences are 

 constant enough to justify a separation of H. repens at a subspecific 

 level. A similar arrangement will possibly be found necessary for the 

 classification of H. repens var. spinulosa, which has not been available 

 for the present study. Although displaying some unusual features, 

 this Mexican spongiUid is therefore Usted in this paper as a dubious 

 synonym until additional material becomes available. 



Heteromeyenia stepanowii (Dybowsky, 1884) 



Plate 9, figures 10-14 



Dosiliai?) stepanowii Dybowsky, 1884a, p. 507; 1884b, p. 476. 



Carterius stepanowii Petr, 1886, p. 93. — Vejdovsky, in Potts, 1887, p. 179. — Potts, 



1887, p. 262.— Lauterborn, 1902, p. 519.— Weltner, 1895, p. 114; 1909, p. 



187.— Wierzejski, 1892, p. 142.— Girod, 1899, p. 113.— Arndt, 1923, p. 77; 



1926, p. 344.— Schroder, 1926, p. 240; 1927b, p. 101. 

 Ephydatia bohemica Petr, 1886, p. 102. — Vejdovsky, in Potts, 1887, p. 179. — 



Weltner, 1895, p. 114. 

 Carterius bohemicus Girod, 1899, p. 54. 

 Carterius stepanowii forma petri Lauterborn, 1902, p. 519. — Schroder, 1926, p. 



243.— Arndt, 1926, p. 344. 

 Carterius stepanowii forma palatinus Lauterborn, 1902, p. 519. — Schroder, 1926, 



p. 244.— Arndt, 1926, p. 344. 

 Carterius stepanowii var. bohemicus Weltner, 1909, p. 189. — Arndt, 1926, p. 344. 

 Heteromeyenia kawamurae Annandale and Kawamura, 1916, p. 14. — Annandale, 



1918a, p. 200.— Gee and Wu, 1928, p. 40.— Gee, 1931e, p. 41. 



