SIBOGLINUM MINUTUM 



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bridle; m - bundle of muscle fibres seen by transparency; tns - mesosoma; mts - metasoma ; 

 p - cuticular plaque; pa - papillae; ps - protosoma; s 2 - groove between the mesosoma and the 

 metasoma ; x 4 - post-tentacular groove between the protosoma and the mesosoma ; sc - dorsal 

 glandular shield; sv - ventral sulcus; / - tentacle; vd - dorsal blood vessel seen by transparency 

 through the body wall. (А, В, С after Ivanov, 1957a.) 



