196 



SCIENCE. 



[N. S. Vol. VII. No. 163. 



Some Grafting Experiments upon Lepidoptera. 



H. E. Ceampton, Je. 



The writer described a series of experi- 

 ments carried on during the spring of 1897, 

 preliminary to a full series now in progress. 

 The operations were performed on pupse of 

 the commoner Saturniidae : P. cynthia, S. ce- 

 cropia, C. promethea and T. polyphemus. They 

 were designed to determine, if possible, be- 

 sides the coalescence power of fragments 

 or nearly complete pupse, as well the color 

 effect, if any, of each component upon, the 

 other. As shown by Mayer and others, the 

 pigmental colors are produced by the chem- 

 ical decomposition of the blood in the empty 

 scale cells ; and, therefore, if two specific- 

 ally different forms were coalesced, recipro- 

 cal color-effects might be looked for. 



Photographs and specimens illustrating 

 the types of operations, as well as some coa- 

 lesced imagines, were exhibited. The first 

 group of operations included homoplastic 

 and heteroplastic unions in natural propor- 

 tions of anterior and posterior halves of 

 pupse. Four out of sixty-one furnished 

 metamorphosed imagines, with the parts 

 perfectly coalesced. A hinder part of the 

 abdomen of a promethea, fused to a cynthia, 

 showed a buffy color, with no trace of its 

 specific red color. 



' Tandem ' unions formed the second 

 group. In these, two pupse, one deprived 

 of its head and the other of the posterior 

 part of its abdomen, were joined. Three 

 out of twenty-seven operations proved suc- 

 cessful, producing compounds with four 

 pairs of wings, six pairs of legs, etc. In 

 heteroplastic operations no definite abnor- 

 mal color- effects were observed. 



' Twin ' unions afforded fourteen pairs of 

 coalesced imagines from a total of sixty -nine 

 operations. Head to head, back to back, 

 tail to tail, and other unions were obtained. 

 Ifo pairs among the heteroplastic opera- 

 tions showed any reciprocal color-effect 

 whatever. 



Regeneration in Planaria maculata. T. H. 



Morgan. 



The remarkable power of regeneration of 

 Planarians has been known for a long time. 

 The more recent results of Van Duyne and 

 Randolph have added many new facts to 

 those already known. The following ac- 

 count gives a few additional observations 

 and experiments to those previously pub- 

 lished. If the planarian {Planaria macu- 

 lata') is cut into cross-pieces all the pieces 

 make new worms unless they be too small. 

 The piece in front of the eyes does not 

 seem to be able to regenerate. Other ex- 

 periments show that this piece is near the 

 linear limit of size below which a piece does 

 not regenerate. In the more anterior cross- 

 pieces the new pharynx appears near the 

 posterior end of the piece ; in the more pos- 

 terior pieces the new pharynx appears in 

 the middle of the piece, and in the last 

 piece the new phai-ynx appears in the 

 middle of the old tissue. Longitudinal 

 pieces cut from the side of the worm, gen- 

 erally form new long worms with the 

 pharynx along the line between the old and 

 new tissue, sometimes, however, in the old 

 tissue. The new median line is often 

 along the middle, or a little to one side of 

 the middle, of the old tissue. Not infre- 

 quently these long pieces from the side de- 

 velop differently. They shorten and be- 

 come crescentic in shape, with the cut edge 

 in the concavity of the crescent. Along the 

 new edge new tissue develops and com- 

 pletely fills up the crescent. This new tis- 

 sue soon develops into a head, with eyes 

 and brain. The median plane of the new 

 animal is at right angles to that of the origi- 

 nal worm. These pieces never elongate, 

 since there is an unbroken ectoderm be- 

 hind, that originally formed the side of the 

 worm. 



Other experiments showed that almost 

 any part of the old tissue had the capacity 

 to form a new pharynx, but the head with 



