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MR.  J.  CURTIS  ON  A  NEW  GENUS 
que  fer^  in  medio  angulos,  in  foemina  minus  conspicuos,  efFormantibus  :  scutellum  semi- 
ovatum.  Corpus  cylindricum.  Elytra  ampla,  subdepressa :  ala  amplse.  Abdomen  elytra 
longitudine  superans,  obtusum,  ad  apicem  in  mare  rotundatum  incurvum,  segmento 
ultimo  discum  magnum,  ovatum,  convexum  efFormante  ;  segmento  basali  (maris)  antic^ 
in  medio  dente  valido  instructo.  Pedes  longissimi,  robusti  (prsesertim  maris),  in  utroque 
sexu  dens^  pubescentes  :  femoribus  tibiis  brevioribus,  quae  (prsesertim  anteriores)  dila- 
tatse,  extern^  3-denticulatse,  dente  apicali  longiore:  tibiis  quatuor  posterioribus  ad  apicem 
breviter  spinosis :  tarsis  totis  pilis  setosis  vestitis,  5-articulatis,  articulis  basalibus 
quatuor  brevibus,  paris  anterioris  in  mare  dilatatis,  articulo  basali  in  foemina  longiore 
et  graciliore,  reliquis  ad  apicem  spinis  validis,  articulo  terminali  longiore,  clavato,  ad 
basin  6-spinoso,  apice  appendiculo  longo  linguiformi ;  tarsis  posterioribus  tibiis  longi- 
oribus  :  unguibus  tarsorum  articulum  terminalem  subsequantibus,  ad  basin  processu  apice 
bisetoso  instructis  ;  foeminse  omnibus,  maris  posticis  tantum,  validis  apice  bifidis. 
Ancistrosoma  is  distinguished  from  neighbouring  genera  by  the  stoutness  of  its  legs 
and  the  sharp  lateral  edges  of  its  thorax :  the  male  is  further  characterized  by  an  acute 
and  rather  long  and  slightly  curved  spine  near  the  base  of  the  abdomen  beneath.  Its 
natural  situation  is  probably  between  Diphucephala,  Dej.,  the  males  of  which  have  a 
bilobed  clypeus,  and  Macrodactylus,  Latr,,  which  is  very  similar  to  our  insect  in  habit, 
and  has  very  long,  but  slender,  legs ;  but  neither  of  these  has  the  little  tooth  at  the 
base  of  the  thorax,  lapping  over  the  scutellum,  and  Ceraspis,  Lep.  and  Serv.,  which  has 
that  character,  is  readily  separated  by  its  long  antenna  and  club,  independently  of  the 
differences  already  mentioned. 
Ancistrosoma  Klugii. 
Anc.  ferrugineum  supra  piceo-nigrum ;  thoracis  margine  elytrorumque  strigis  sex  albidis. 
Long,  maris  12  lin. ;  foemin2e  plerumque  minor. 
Hab.  in  Peruvia. 
Description.  Ferruginous  ;  base  of  the  head  blackish,  punctured,  and  clothed  with 
short  ochreous  hairs,  with  a  waved  elevated  line  across  the  middle,  extending  over  the 
inner  margin  of  the  eyes  :  thorax  piceous  black,  with  a  punctured  channel  down  the 
middle,  the  margins  punctured,  ferruginous  and  whitish  with  short  hairs ;  having  two 
large  dull  ovate  spots  at  the  base  in  the  female :  scutellum  clothed  with  ochreous 
hairs :  elytra  piceous  black,  with  three  broad  punctured  furrows  on  each,  white  with 
short  hairs,  the  sutural  one  not  reaching  the  base,  but  extending  round  the  apex,  the 
second  neither  extending  to  the  base  nor  apex,  and  the  outer  one  still  shorter :  legs 
thickly  clothed  with  long  orange  or  bright  ochreous  hairs,  excepting  the  anterior  tibia : 
