[39] ENTOZOA OF MARINE FISHES OF NEW ENGLAND. 491 
convex. In others they could not all be made out definitely, but enough 
could be made out to show that they were irregularly placed. 
Habitat.—Common Eel (Anguilla vulgaris); intestine; 12 specimens, 
6 and 2; September 2, 1885. Dusky Shark (Carcharias obscurus); 1 
specimen, 6; August, 1884. Wood’s Holl, Mass. 
Of the following specimens of which measurements were made, No. 
1is a female, Nos. 2 and 3 are males. No. 3 is the specimen obtained 
from the spiral intestine of C. obscurus : 







Dimensions. No.1, 9 | No.2, ¢ | No.3, ¢ 
mm, mm. mm 
HEMP TMIOL SPOCINOEMN. < oancic cw celnm es cnlererm sls wiwvliew semncs sunie ceiancue ans 9. 50 6. 44 4. 60 
Length of proboscis. ..-.---.---------.0- 22-22 eee ee cee e eee e ee cen ees 0.17 0. 105 0.16 
Breadth of proboscis, apex ----.-. 2-6 2. een ee ne ewe nee neneseceossne. 0.17 0.14 ;- 0.162 
Breadth of proboscis, base-\..-.....-.---.-e-.02- 2 ecee nese scence nn cenee 0.15 0.12 0, 132 
Length of proboscis sheath... ~~... 20. ---- ene nec ee en nes seeene scenes. OF 4G) eetrelnin act 0. 30 
EBM OR PLGDOSCIS:AUCBUD = )ccecm cis cccce\scnsccsconeeese sie ne tacseescos|-nenee eeesleeeeee ee 0,12 
Lan cT @p VETO UE As Soa nee Gog nose re beCO OE DOS CSE EDE Ge Sc chp eee Manic 1. 50 1, 50 1.40 
Pee OIMHOLY, MIGOLION oink Clete sae ae sn ast clas sine cde ameneecd seats lice cee che = ae cee 0,19 
PAM Hee DOM yOVOMLCS bene cic tesiae ademas a eine ice wicinoeaisn cise omen eees |e seaicn cna eeemcoeaee 0. 50 
eset O SHOU ys NORLOLIOL ON: «jajech wows cescccianstsicedsct coe cobs santas oc ncae| Saaeeeeees 0, 16 
Millimeters. 
Length of hooks in front row..-.--..-.--.------ Safomiaetd sle/siuisiuloiciel else ewetdnteite roe 
2 0, 090 
PEPIN 11, HECOLC TOW 2 = sects ciaese ncccie yc scas sas seu Cepeen cee ntenate 0. 023 
Menewn onrecurved part:of front hooks. 2. -..).25. 2.02.5 /2-2-6 sss ak 0. 061 
SETTER EIS AL OLS tae ae hole ada Sou cee Gas LOSI aL Witie LI ead he oe 0. 035 
ENE OW Birt oa iis a wins wa Na hi ie a jace\ntd 2 Sield So wtxiwis = Slo viaceyauss' gay cebianesh see 0. 017 
Length of ovarian masses much greater than ova, circular and oval, with diame- 
ters as much as 0.1™™, others as low as 0.04™™, 
I confess no small degree of perplexity in identifying this species as 
H. agilis.- The arrangement and character of the hooks of the pro- 
boscis ally it closely with this species and a little less closely with 2. 
claviceys Zeder. The lemnisci are not so long in proportion to the 
length of the animal asin either of the above-named species. This is 
about the only character that hints at a probable specific difference 
which is sufficient to justify the separation of the specimens under con- 
sideration from either of the above species. The presence or absence 
of the so-called neck is rather a doubtful feature at best. 
_ While there are no distinctive characters which seem to my mind to 
be important enough to justify the erection of a new species, there are 
certainly strong reasons afforded for uniting JL. claviceps and LE. tu- 
berosus, which is, indeed, proposed by Dujardin (op. cit., p. 538) and 
accepted by Diesing, who does not mention EH. claviceps in his revision, 
and including both under H. agilis Rudolphi. 
In the absence of frgures of these species I must content myself at 
present with referring these specimens to HL. agilis. 
With regard to the single specimen found in the spiral valve of Car- 
charias obscurus, it may be well to observe that its presence there may 
be accounted for by supposing it to have been introduced in the adult: 
