The Protochordata 465 



in all the warm seas. In Spengel's recent paper, "Die Benen- 

 nung der Enteropneusten-Gattungen," three famihes are recog- 

 nized with nine genera and numerous species. At least seven 

 species are now known from the Pacific Coast of North America. 

 Family Harrimaniidae. — In Harriuiaiiia viacidosa, lately de- 

 scribed by Dr. Ritter from Alaska, the 



eggs are large, with much food yolk, 

 and the process of development is 

 probably, without Tornaria stage. A 

 second species of Harriniania (H. kiip- 

 jeri) is now recognized from Norway 

 and Greenland. This genus is the sim- 

 plest in structure among all the Enter- ^ 



Fig. 277. — Harrunama macii- 



opneustans and may be regarded as the losa (Ritter), the lowest of 

 lowest of known Chordates, the most Ltpt^rfron. "Tx.^^. 

 worm-like of back-boned animals. (After Ritter.) 



In Dolichoglossns ko'valevskii the species studied by Bateson 

 on the Virginia coast, the same simplicity of development 

 occurs. This genus, with a third, Stereobalanus {canadensis), 

 constitutes in Spengel's system the family of HarrimaniidcB. 



Balanoglossidae. — The family GlandicepitidcB contains the genera 

 Glandiceps, Spengelia, and Schizocardium. In the BalanoglossidcB 

 (Ptychoderid(£ of Spengel) the eggs are very small and numerous, 

 with little food yolk. The species in this family pass through 

 the Tornaria stage above described, a condition strikingly like 

 that of the larval starfish. This fact has given rise to the 

 suggestion that the Enteropneusta have a real affinity with the 

 Echinoderms. 



The Balanoglossidcc include the genera Glossohalanus, Bala- 

 noglossus, and Ptychodera, the latter the oldest known member 

 of the group, its type, Ptychodera ftava, having been described 

 by Eschscholtz from the Pacific Coast in 1825, while Balaiio- 

 glossiis clavigeriis was found by Delia Chiaje in 1829. 



Low Organization of Harrimaniidae. — Apparency the Harri- 

 maniida:, with simpler structure, more extensive notochord, and 

 direct development, should be placed at the bottom as the most 

 primitive of the Enteropneustan series. Dr. Willey, however, 

 regards its characters as due to degeneration, and considers the 



