[Fcliruary — Marcli 1SS9. 



PSYCHE. 



179 



The resemblance of some seeds or 

 fruits to dirterent kinds of insects or 

 other arthropods has several times been 

 commented on. Perhaps it is still an 

 open question whether or not this is 

 mimicry, but it has been so regarded by 

 a number of naturalists, being held in 

 some cases to secure dissemination bv 

 insectivorous birds, etc., and in others 

 to render the detection of the seed by 

 graminivorous birds, difficult. Sugges- 

 tions are not wanting that in some of 

 these resemblances, and some other 

 seminal peculiarities, adaptations exist 

 for securing dissemination through the 

 agency of ants. Mr. Charles Robert- 

 son tells me that the arils of Sanguin- 

 aria seeds possess an attraction for ants, 

 which drag the seeds oft' for consid- 

 erable distances. I cannot say whether 

 they finally eat these fleshy appendages. 

 According to Limdstrom (i6, 79), 

 Melainpyrum seeds resemlile ant pupae 

 in size and form, and, as he believes, in 

 odor also, to such an extent that ants 

 are deceived into caring for them as if 

 they were their own pupae, until the 

 mistake is discovered. Mimicrv, such 

 as he suggests, is a very difficult thing 

 to provx to the satisfaction of unbiased 

 biologists, but observations cited by him 

 would seem to show that unusual atten- 

 tion is reallv paid to these seeds bv ants 

 which do not subsequently make use of 

 them for food. The bracts of some spe- 

 cies of this genus bear extranuptial nec- 

 tar-glands, which Rathay (22 ), who 

 studied them carefullv, could not ex- 

 plain by the protective theories of 

 Delpino and Belt, or Kerner, though 



they arc visited by ants. As the latter 

 are thus attracted close to the fruit, 

 Lundstrom suggests that the office of 

 these nectar-glands may stand in close 

 relation with the supposed mimicry 

 observed in the seeds, — but this entire 

 subject, while full of suggestion, is still 

 in need of careful and comparative 

 study. 



References. 



This list of papers mentioned in the preced- 

 ing pages makes no claim to completeness. 

 Many references to contributions as important 

 as some of these might have been added, but 

 the student who examines those that are cited 

 here will find in them references to all that 

 has been published elsewhere. A rather re- 

 cent and very useful bibliography, although 

 it is not complete, is that of Huth. — Myrme- 

 cophile und myrmecophobe Pflanzen, Berlin, 

 1S87, — as no. 7 of his samnlung naturwiss- 

 enschaftlichen Vortrage. 



1. Beccari, O Piante ospitatrici ossia 

 piante formicarie della Malesiae della Parua- 

 sia. "Malesia," 1884, fasc. i and 2: 1885. 

 fasc. 3. A very full abstract in Engler's Bot 

 jahrbiicher. 1886, v. 7, p. 51-72. 



2. Belt. T. The naturalist in nicaragua. 

 London. 1874. 



3. C.\RUEL, T. Illustrazione di una Rubi- 

 acea del genere Myrmecodia (Nuovo Gior- 

 naie bot. Ital. 1872, v. 4, p. 170). Includes 

 quotations from Beccari's manuscript notes. 



4. Darwin, C. Fritz Mueller on Brazil. 

 Kitchen middens, habits of ants. etc. (Na- 

 ture, 1876, v. 13, p. 304-5.) 



5. Darwin, F. On the glandular bodies on 

 Acacia xphaerocephala and Cecrofia peltata 

 serving as food for ants. With an appendix 

 on the nectar-glands of the common brake 

 fern. Pteris aquilina. (Journ. Linn, soc, Bot., 

 V. 15, p. 398-409.) 



6. Delpino. F. Ulteriori osservazioni 

 suila dicogamia nei regno vegetale. 2. fasc. 2. 



