WIDERSTEN: ANTHOZOA FROM EASTERN COAST OF UNITED STATES 



100/jm 



mesenteries are strong, five to eight pairs being 

 circumscribed, and sometimes reniform (Figure 

 9B), those of the other perfect mesenteries being 

 diffuse but with a tendency to become restricted. 

 The parietobasilar muscles are rather strong, 

 forming distinct lamellae on the peripheral parts 

 of the mesenteries (Figure 9C). The imperfect 

 mesenteries lack retractors as well as filaments 

 (always ?) (Figure 9E). In those specimens where 

 genital organs were found, these were always 

 developed in perfect mesenteries. The acontia are 

 numerous and provided with basitrichs. Only one 

 imperforate cinclis (Figure 9D) was found in the 

 sections of the species. Probably the species re- 

 produces asexually by laceration. The proximal 

 part of the column and the often wide pedal disc 

 are often asymmetrical. 



NEMATOCYSTS.-Co/wmn: basitrichs (21 x 

 2.7 -) 23-27 X 3.3-3.8, 31-39 x 4.4; atrichs 19-20 

 X 4.4-4.9, 39-45 x 12.5-14.7. Tentacles: basitrichs 

 11 X 1.6-2.2 - 33 X 3.3-3.8; atrichs (not common; 



in many tentacles completely missing) 39 x 13.1 - 

 49 X 5.5, spirocysts (very numerous, and in 

 some of the studied specimens with a very small 

 variation in size) 17 x 2.2 - 34 x 3.8-4.9. Actino- 

 pharynx: basitrichs 14 x 2.2 - 32 x 3.8; microba- 

 sic p-mastigophors 17-26 x 3.8-4.4. Filaments: 

 basitrichs 12-15 x 2.2; microbasic p-mastigophors 

 13 X 3.3 - 26 X 4.3-5.5. Acontia: basitrichs 13- 

 16 X 2.2-2.7, 33 x 3.3 - 45 x 3.8 /xm. 



In specimens from 40°03'N, there were also 

 found atrichs in the filaments (12 x 6, 18 x 

 4.9 - 24 X 5 jLtm) as well as holotrichs (22 x 4.9 - 

 24 X Sjiim). Both these nematocyst types are 

 probably residues of intaken food-the specimens 

 in question were found together with some in- 

 dividuals of Epizoanthus incrustatus. 



This species, first described by Verrill (1883) as 

 Sagartia spongicola, has been the object of later 

 investigations by, e.g., McMurrich (1898) and 

 Carlgren (1950). Carlgren (1950) (on the basis of 

 acontian armament with basitrichs ?) described 

 the species as a hormathiid and a member of the 



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