^°i«9i!''] PKOCKEDINGS OF THH NATIONAL MrSEl'M. 585 



Nees's observation as "proof that tlu^ KiuyioiiiM'. aio, not all parasitic," 

 and j>oes on to say: " Whetlicr onc^ species of this family is sometimes 

 parasitic ou other insects and sometimes herbivorous, and has thns the 

 choice of two ways of perpetuating its existence, has yet to be ascer- 

 tained." 



The lenjithy discnssion, extending; over man}' years, conciTiiing the 

 true habit of the American Joint Worm {Lsosomtt kordii), ami Imw 

 even alter the i)roof of its phytophagic liabit addnced by Harris, I'itcli, 

 and Walsh (the latter chanyin<;' from the wrong to the right side of tiie 

 (piestion after ascertaining the generic; distinction of tin; Joint Woiin 

 from Eurytomd), thi}. fact was still not accepted by many lOnropean ento 

 mologists as late as 1882 need not be elaborated here — it is common 

 information to all American entomologists. Sim^e the publication (>l' 

 liiloy's articles on Isosoma iritici and the admirable summary of the 

 entire subject by the veteran Westwood (Trans. Kntom. Soc. Lon<l., 

 1882, 307-.'J27) no word of opposition has been a<lvanced t<> tlic concln- 

 sion that TsoHoma at least is i)hyto|)hagic. 



In the early concensus of European opinion against llie views of 

 American entomologists on this important [)oinl, however, we must not 

 lose sight of the fact that three Dutch observers, Ititsema, Weyen- 

 bergh, and Snellen von \'ollenhoven, had at least as early as 1870 proven 

 that a gall on beach grass {AmmophHa annul iuacca) was produced hy 

 Eurytoma (?) lonnipcnnis, the first observation having been made lt.\ a 

 brother of H. Kitsema in 1S(;7, (See Archives Neerlandaises dis 

 Sciences Exactes, V, 1S7(>, and Tijdschrift voor Entonu)logie, Second 

 Series, Yi, 1871, pp. 118.) This species is probably not a Enrytonui, but 

 an lansoma, although 1 can timl no published statement to this effect. It 

 is not included by Mayr, however, among the species of Ihirytomn. 



The grape-seed feeders formerly jilaced in J.sosoma belong to Evoxy- 

 soma Ashm., and ujipublished notes of the Division of I'ntomology 

 show that IJiirytomacharis Ashm., I.soso)ii()rj>ha Ashm., and PhiUwhyra 

 Hal., are also gall-makers, (The type of the last named genus was 

 found in straw roofs lu'ar Lucca, Italy). These three genera are, how- 

 ever, much more closely related structurally to Isosoma than to Eury- 

 toma, Dccatoma, or other eurytomine genera. Others of Ashmead's re- 

 cent genera resembling Isosoma will probabi}' also be found to have the 

 phytophagic habit. 



As before mentioned, the habit of Eurytoma has been (juestioned by 

 Walker largely on the strength of Nees's observation. \Vestwood (htr. 

 cit.) says of his ( 'eylonese Eurytoma taprohanica, " I have but little 

 doubt that this beautiful spi'cies is the real maker of the gall (on Eicus) 

 from which si)ecimens of both sexes have been reared." No good proof, 

 however, has ever been advanced to show that Eurytoma proper is ever 

 anything but parasitic, while the possible hypothesis that it may be in- 

 quilinous in the gall from which it is so abnmhnitly reared is to a great 

 extent disproveu by my observations on Eurytoma prunivola, larvie of 



