142 ON THE STRUCTURE OF THE ROTIFERA. 



The genus Lindia, Duj., is said to be witliout cilia on the head, whicli 

 I much doubt. 



VI. Without foot. 



1. Albertia. 



Includes the A. vermiculus, found by Dujardin in the abdominal cavity 

 of the Earthworm, and in the intestine of the Limacina ; and A. crystal- 

 Una, discovered by Schultze in the intestine of Nais littoralis. 



I have long ago noticed a similar Albertia in the intestine of Nais elin- 

 guis. On com[)aring the drawings I then made with the figures given by 

 Schultze, I perceive the closest correspondence with his tig. 13. (Beitrage 

 zur Naturgesch d. Turbellarien, Taf VII. &c.) So that it may probably 

 be the same species. 



B. Figure sacciform. 

 I. Foot short. 



1. NoTOMMATA clavalata, inyrmeleo, syrinx, Ehr. 



2. DiGLENA lacustris, Ehr. 



IT. Foot absent. 



1. NoTOMMATA anglica, Dalrymple ; Sieholdii, n. sp. 



2. PoLYAKTHRA platyptera, Ehr. 



3. Triarthra longiseta, mystacina, Ehr. 



4. AscoMORPHA helvetica, Perty ; germanica, u. sp. 



C. Figure compressed. 

 a. Depressed from above downwards. 



I. With a foot. 



1. EucHLANis triquetra, Hornemanni, luna, macrura, dilatata, 



lynceus, Ehr. ; unisetata, n. sp. ; bicarinata, n. sp. {E. 

 bicarinata, Perty, I consider a Salpina). 



2. Lepadella ovalis, emarginata, salpina, Ehr. 



3. MoNOSTYLA cornuta, quadridentata, lunaris, carinata, Ehr. 



4. Metopidia lepadella, acuminata, trip)tera, Ehr. 



5. Stephanops lamellaris, midicus, cirratus, Ehr. (Dujardin 



declares that St. muticus is Lepjadella ovalis). 



6. Squamella bractea, oblonga, Ehr. 



7. NoTOGONiA Ehrenbergii, Perty. 



8. Noteus quadricornis, Ehr. 



9. Brachionus pala, amphiceros, urceolaris, rubeus, MUlleri, 



brevispinis, Baheri, polyacanthus, militaris, Ehr. 

 10. Pterodina patina, elliptica, clypeata, Ehr. 



II. Foot absent. 



1. Anurea qi(adridentata, squaniida, falculata, curvicwnis, bi- 

 remis, striata, inermis, acuminata, foliacea, stipitata, tes- 

 tudo, serrulata, aculeata, valga, Ehr. 



/3. Laterally compressed. 



1. Salpina mucronata, spinigera, ventralis, redunca, brevispina, 



bicarinata, Ehr. 



2. Mastigocerca carinata, Ehr. 



3. MoNURA colurus, dtdcis, Ehr. 



4. CoLURUS micinatus, bicusjndatus, caudatus, dejlexus, Ehr. 



