SCIENCE 



[N. S. Vol. XXVII. No. 691 



sired are able to pass the examinations 

 without special preparation, and it is not 

 desired to afford any particular oppor- 

 tunity for such preparation. 



With the exception of a few small 

 laboratories where the field work is limited 

 and promotion is not offered, the great 

 majority of appointments to the various 

 government laboratories are to subordinate 

 positions and higher positions are filled by 

 promotion whenever possible. Special 

 qualifications are, therefore, not usually 

 required. 



I wish to emphasize the fact that every 

 appointee should have pursued a broad 

 general course of study. The argument is 

 frequently made, and it is doubtless true, 

 that the work for which the majority of 

 appointments are primarily made, that is, 

 the ordinary routine work of the labora- 

 tory, could be as well performed at the 

 beginning by men who are not college 

 graduates, and frequently by men whose 

 training in chemistry itself has been very 

 incomplete. It is found, however, that 

 while such men may be satisfactory at the 

 beginning, their potential power is limited. 

 Men with special training are frequently 

 desired for the purpose of conducting spe- 

 cial investigations. This special training, 

 however, should have been received in post- 

 graduate study. The ability to conduct 

 research work that is constantly required, 

 the resource essential to emergencies and 

 even the initiative required by those who 

 take a responsible part in the routine work 

 of the laboratory are rarely secured except 

 in men with broad fundamental training. 



"W. D. BiGELOW 



THE AMERICAN SOCIETY OF ZOOLOGISTS 



II. 

 A Comparison of the Cephalic Organs in 



Certain Sipunculids: John H. Geeould, 



Dartmouth College. 



A comparison was made between the 



cephalic organs in Phascolosoma verrillii — 

 an undescribed species from Vineyard 

 Sound and Buzzards Bay, covered with 

 prominent papillae and characterized by 

 having only a single pair of retractor 

 muscles (ventral)— and the corresponding 

 organs in Sipunculus niidus and in other 

 forms. 



P. verrillii has not only the ciliated 

 nuchal organ of other Phascolosomas {P. 

 gouldii, P. vidgare) but also a cerebral 

 organ, that lies superficially between the 

 nuchal organ and the mouth. In a young 

 (postlarval) individual it forms a rounded 

 elevation of surface epithelium dorsal to 

 the mouth, but ventral, or oral, to the 

 nuchal organ. In the adult (P. verrillii, 

 P. gouldii) it becomes less conspicuous and 

 elongated transversely in the frontal plane. 

 It is closely connected with the brain 

 (supra-esophageal ganglion) by a pair of 

 large lateral cords containing (1) a pair of 

 ocular tubes, which open dorso-laterally 

 upon the surface of the cerebral organ, 

 and (2), mesial to each ocular tube, the 

 special neurones and a pair of sensory pits 

 of the cerebral organ itself. 



The cerebral organ in Sipunculus nudus, 

 as Ward and, later, Metalnikoff have 

 shown, projects into the bottom of a long 

 tube which, opening upon the dorsal sur- 

 face of the body slightly behind the ten- 

 tacles, runs backward and inward to the 

 cerebral organ. The latter and the cor- 

 responding organ upon the surface of the 

 head in Phascolosoma have precisely simi- 

 lar relations to the brain ; and ocular tubes 

 open upon the surface of the cerebral 

 organ in both forms. Phymosoma {Phys- 

 cosoma) varians, as described by Shipley, 

 shows an intermediate stage between the 

 primitive condition in Phascolosoma, in 

 which the cerebral organ is superficial, and 

 that in Sipunculus. 



Ocular tubes with pigmented walls were 

 found in a specimen of Sipunculus nudus 



